In the offseason, the standard for these lists is pretty much universal: A prospect refers to a player who retains rookie status, meaning no more than 130 at-bats or 50 innings pitched in the major leagues.

Many adopt the same standard during the season, which gets a little messy, I think. The list I've put together here figures to be referenced well beyond the date it's published, after all, and having to determine retrospectively if a player was excluded because he had already crossed a playing time threshold or because he simply wasn't good enough seems like a frustrating and unrealistic task for Joe Reader.

So I simplify the standard for my midseason top 25: If a player has already appeared in the majors, he doesn't qualify. It avoids confusion and prevents the list from being overrun by those who've already gotten plenty of runtime in Fantasy advice columns, such as Yordan Alvarez, Keston Hiura and Zac Gallen. Of course, it also excludes prospects who you may not realize have already debuted, such as Kyle Tucker, Luis Urias and Carter Kieboom, but hey, this is me making you aware that they have.

Also, there are no 2019 draft picks here. Until they have some numbers to their names, it's too speculative how they compare to the best of what's out there. I'd venture to guess the top three picks — Adley Rutschman, Bobby Witt and Andrew Vaughn — are at least deserving of consideration in what's a weaker-than-usual group, but narrowing down exactly where they'd rank is not something I'm prepared to do yet.

As always, a Fantasy Baseball-focused rank list places a lower emphasis on defense and a higher emphasis on readiness, so keep that in mind.

All stats are updated through Tuesday, July 2.

1. Wander Franco, SS, Rays

Age: 18
2019 levels: low Class A, high Class A
2019 stats: .337 BA (255 AB), 8 HR, 15 SB, .955 OPS, 35 BB, 20 K
Because proximity to the majors is a point of emphasis for this list, it's tempting to go against consensus and flip-flop Franco with No. 2 in these rankings. But the approach is so advanced for a high school-age kid, and the tools are already beginning to play up. Now that Franco is doing it at high-A ball, he's on a rocket ship straight to the top.
Second-half callup is ... not happening.

2. Bo Bichette, SS, Blue Jays

Age: 21
2019 levels: high Class A, Triple-A
2019 stats: .318 BA (132 AB), 3 HR, 11 2B, 12 SB, .886 OPS, 18 BB, 30 K 
With the way he's swung the bat at Triple-A since returning from a broken hand in mid-June, Bichette looks like he'll quickly join Vladimir Guerrero and Cavan Biggio to give the Blue Jays an impossibly cute trio of second-generation stars. He's sort of the best of both worlds, too, showing an aptitude for stealing bases along with tremendous bat skills, and his swing generates so much torque that the power will come.
Second-half callup is ... likely.

3. Jo Adell, OF, Angels

Age: 20
2019 levels: high Class A, Double-A
2019 stats: .352 BA (108 AB), 6 HR, 4 SB, 1.023 OPS, 8 BB, 26 K 
Like Bichette, injuries (his being to his hamstring and ankle) may be all that's prevented Adell from ascending already, which is saying something given how young he is. The 10th pick in the 2017 draft has made quick work of the minors, demonstrating every tool you could want except maybe for on-base skills.
Second-half callup is ... possible.

4. Jesus Luzardo, SP, Athletics

Age: 21
2019 levels: high Class A, Triple-A
2019 stats: 2-0, 2.79 ERA, 0.98 WHIP, 19 1/3 IP, 2 BB, 25 K
A Grade 2 lat strain suffered in his latest rehab start dropped Luzardo a couple spots in these rankings and put a roadblock in what seemed like an easy path to the bigs. But whether it's this year or next, he'll arrive ready to assist in Fantasy. The fastball and changeup both rate as plus-plus, the curveball is no slouch itself, and the command he already has of that arsenal is something special.
Second-half callup is ... possible.

5. Casey Mize, SP, Tigers

Age: 22
2019 levels: high Class A, Double-A
2019 stats: 8-0, 0.92 ERA, 0.69 WHIP, 78 IP, 12 BB, 75 K 
Though the Tigers aren't at a point in their rebuild when they're looking to break in top prospects, the first overall pick in last year's draft was making sure they had little say in the matter, so thoroughly dominating with his four-pitch arsenal and advanced command that it made his K/9 look bad. Nobody was getting on base against him, which gave him fewer opportunities for strikeouts. A sore shoulder has slowed his roll for now, but he's coming fast.
Second-half callup is ... unlikely.

6. MacKenzie Gore, SP, Padres

Age: 20
2019 levels: high Class A
2019 stats: 7-1, 1.02 ERA, 0.71 WHIP, 79 1/3 IP, 20 BB, 110 K
Nobody is getting on base against Gore either, and yet look at his strikeout rate. Clearly, the third overall pick in the 2017 draft is a force to be reckoned with, having overcome the blister issues that sidetracked him in 2018, but the Padres have so far moved him at a cautious pace.
Second-half callup is ... unlikely.

7. Luis Robert, OF, White Sox

Age: 21
2019 levels: high Class A, Double-A
2019 stats: .349 BA (289 AB), 15 HR, 26 SB, 1.017 OPS, 17 BB, 74 K
The biggest riser among hitting prospects this year arrived from Cuba to much fanfare a couple years back but didn't hit a single home run during an injury-plagued 2018. Most prospect evaluators kept the faith, though, and the athletic 21-year-old has rewarded them with impossibly good production that's made all the more enticing by his stolen base prowess.
Second-half callup is ... unlikely.

8. Alex Kirilloff, OF, Twins

Age: 21
2019 levels: Double-A
2019 stats: .275 BA (160 AB), 2 HR, 12 2B, .763 OPS, 18 BB, 38 K
Yet another top prospect whose ascent has been derailed by injuries, his being primarily a wrist issue early this year, Kirilloff nonetheless still has all the luster from his breakthrough 2018, when he came back from Tommy John surgery to hit .348 with a .970 OPS. Still, the Double-A level is a critical one for establishing the legitimacy of a prospect, and he'll need to deliver there soon.
Second-half callup is ... unlikely.

9. Forrest Whitley, SP, Astros

Age: 21
2019 levels: Triple-A
2019 stats: 0-3, 12.21 ERA, 2.06 WHIP, 24 1/3 IP, 15 BB, 29 K 
The fact Whitley's prospect standing can survive the horrors of this season shows just how highly regarded he was at the start of it: the consensus top overall pitching prospect whose overpowering arsenal drew comparisons to Noah Syndergaard. He has sat out the past six weeks due to shoulder fatigue, but stuff was less the issue during his struggles than command, which seems correctable.
Second-half callup is ... unlikely.

10. Royce Lewis, SS, Twins

Age: 20
2019 levels: high Class A
2019 stats: .235 BA (315 AB), 6 HR, 13 SB, .635 OPS, 20 BB, 74 K
Here's another struggling prospect whose pedigree is good enough to carry him. Lewis is a former No. 1 overall pick who tore up the lower minors but is having trouble adjusting to high-A ball for the second straight year. There are a number of theories as to why he's struggling, such as mechanics, approach and the Florida State League being tough on hitters, but the bottom line is he deserves more time.
Second-half callup is ... not happening.

11. Matt Manning, SP, Tigers

Age: 21
2019 levels: Double-A
2019 stats: 6-4, 2.77 ERA, 1.04 WHIP, 91 IP, 31 BB, 106 K
With an electrifying fastball and hard-breaking curve, Manning has been a strikeout machine since the Tigers drafted him ninth overall in 2016, but concerns about an inconsistent delivery, particularly given his 6-foot-6 frame, had consistently dampened the prospect hype. Now that he's doing it at Double-A, though, it's time to soak it in.
Second-half callup is ... unlikely.

12. Ian Anderson, SP, Braves

Age: 21
2019 levels: Double-A
2019 stats: 6-5, 2.94 ERA, 1.20 WHIP, 85 2/3 IP, 43 BB, 113 K
The highest Braves draft pick during their rebuild (third overall in 2016) may turn out to be the best of the many pitching prospects they accumulated during that time. Though the control hasn't always been there at Double-A, the stuff certainly has, and it's all been pretty impressive since about mid-May, positioning him for a possible promotion during the stretch run.
Second-half callup is ... possible.

13. Joey Bart, C, Giants

Age: 22
2019 levels: high Class A
2019 stats: .256 BA (121 AB), 6 HR, .784 OPS, 7 BB, 27 K    
The buzz started for Bart in spring training and was only quieted early on because he broke his hand. In the little action he has seen since returning, the numbers are no more than solid, but scouts seem to have already made up their minds about this guy, who defends well and makes enough contact to get the most out of his all-fields power. How long can a quickly fading Buster Posey hold him off?
Second-half callup is ... unlikely.

14. Gavin Lux, SS, Dodgers

Age: 21
2019 levels: Double-A, Triple-A
2019 stats: .325 BA (280 AB), 14 HR, 7 SB, .934 OPS, 31 BB, 65 K
Last year's power breakthrough has carried over to this year, making Lux one of the minors' most productive hitters and yet another cornerstone talent for a Dodgers system that never seems to run out. Having recently moved up to Triple-A, he'll need more reps at second base to position himself to become Corey Seager's double-play partner, perhaps as early as next year.
Second-half callup is ... possible.

15. A.J. Puk, SP, Athletics

Age: 24
2019 levels: high Class A, Double-A
2019 stats: 0-0, 6.14 ERA, 1.77 WHIP, 7 1/3 IP, 5 BB, 13 K
Puk, you may remember, was pushing for a rotation spot last spring before succumbing to Tommy John surgery, so while his rehab assignment has been less than dazzling, he's already shown himself to be more or less a finished product. Though control is an issue, he piles up strikeouts thanks to a fastball-slider combo that's made all the more dizzying by his 6-foot-7 reach, a la Randy Johnson.
Second-half callup is ... expected.

16. Jarred Kelenic, OF, Mariners

Age: 19
2019 levels: low Class A, high Class A
2019 stats: .290 BA (262 AB), 14 HR, 11 SB, .917 OPS, 31 BB, 66 K 
The sixth overall pick a year ago and the main piece that sent Edwin Diaz and Robinson Cano to the Mets this offseason, Kelenic has put on a clinic in the lower minors, living up to the most optimistic scouting reports with a steady demonstration of power, speed and on-base skills.
Second-half callup is ... not happening.

17. Cristian Pache, OF, Braves

Age: 20
2019 levels: Double-A
2019 stats: .295 BA (292 AB), 11 HR, 6 3B, 21 2B, .877 OPS, 26 BB, 73 K
It's a terribly unfair comparison and yet one that has to be made for toolsy prospect who mostly stood out for his defense until that day when everything clicked and he suddenly became an offensive force against what should have been superior competition. OK, so Ronald Acuna's breakthrough was more telegraphed than Pache's, but the way the latter's contact and power skills have spiked over the past month is reminiscent.
Second-half callup is ... possible.

18. Alec Bohm, 3B, Phillies

Age: 22
2019 levels: low Class A, high Class A, Double-A
2019 stats: .331 BA (284 AB), 10 HR, 22 2B, .945 OPS, 35 BB, 46 K
Though the Phillies picked him third overall last year, Bohm's failure to deliver in the weeks that followed made him a wild card in preseason prospect rankings. He's more than made up for it this year, though, mashing from Day 1 and sustaining it even with two moves up the minor-league ladder. The contact and on-base skills are especially promising given that power is supposed to be his best tool.
Second-half callup is ... possible.

19. Matthew Liberatore, SP, Rays

Age: 19
2019 levels: low Class A
2019 stats: 6-1, 1.50 ERA, 0.92 WHIP, 48 IP, 15 BB, 49 K
After being held back in extended spring training as a way to limit his innings, Liberatore has come of it looking yet again like there's no holding him back, working deep and efficiently with three plus pitches, a clean and repeatable delivery and poise beyond his years. Sort of like Mike Soroka in that he pitches so much older than he actually is, Liberatore could move similarly fast.
Second-half callup is ... not happening.

20. Nate Pearson, SP, Blue Jays

Age: 22
2019 levels: high Class A, Double-A 
2019 stats: 3-1, 1.89 ERA, 0.78 WHIP, 47 2/3 IP, 8 BB, 66 K
It may have gotten lost amid the strained back and fractured forearm that cost him all but 1 2/3 innings last season, but Pearson has stuff coming out of his eyeballs, regularly lighting up the radar gun with 102 mph fastballs. The Blue Jays, fittingly, have been uber careful with him, limiting him to just two innings every other start, which of course raises workload concerns.
Second-half callup is ... unlikely.

21. Sixto Sanchez, SP, Marlins

Age: 20
2019 levels: high Class A, Double-A
2019 stats: 3-6, 4.05 ERA, 1.31 WHIP, 66 2/3 IP, 14 BB, 64 K  
The prize of the J.T. Realmuto deal, Sanchez has yet to deliver numbers befitting a future ace, which is how he's widely regarded. The stuff and control still earn high marks, but he remains a bit of a project, particularly since injuries have stunted his innings accumulation.
Second-half callup is ... not happening.

22. Brent Honeywell, SP, Rays

Age: 24
2019 levels: has not played due to injury
2017 stats: 13-9, 3.49 ERA, 1.24 WHIP, 136 2/3 IP, 35 BB, 172 K
Honeywell looked like a near fully formed ace on the verge of landing a big-league job when he succumbed to Tommy John surgery last spring, and then on the road back this year, he fractured the same elbow he had just had repaired. It's sort of amazing he still ranks so high coming off consecutive catastrophic injuries to that oh-so-important body part, but the prospect field gets much iffier from here.
Second-half callup is ... not happening.

23. Taylor Trammell, OF, Reds

Age: 21
2019 levels: Double-A 
2019 stats: .247 BA (235 AB), 5 HR, 15 SB, .717 OPS, 46 BB, 68 K 
Trammell looked like he was verging on greatness last year, but the high preseason ranking was in anticipation of him taking another step forward, not back. The good news is that he continues to steal bases and draw walks, which are more important skills than power in an era when power comes so easily.
Second-half callup is ... unlikely.

24. Drew Waters, OF, Braves

Age: 20
2019 levels: Double-A
2019 stats: .323 BA (319 AB), 5 HR, 8 3B, 26 2B, .869 OPS, 20 BB, 97 K
An interesting prospect in that the way he stands out statistically is so obviously unsustainable — high BABIP and all — and yet the underlying bat skills are so impressive that it still points to a high ceiling. Waters will need to cut down on the strikeouts or improve his home run production, but given how young he is for the level he's at, both seem plenty attainable still.
Second-half callup is ... unlikely.

25. Isan Diaz, 2B, Marlins

Age: 23
2019 levels: Triple-A
2019 stats: .296 BA (287 AB), 20 HR, .968 OPS, 38 BB, 71 K
Though he won't appear this high on any other prospects list, Diaz has clearly positioned himself as the Marlins' second baseman of the future, perhaps as early as the second half, and opportunity is of course half the battle. He was once highly regarded — top-100, even — so his re-emergence as a power hitter is deserving of more attention than it's gotten, especially since it coincides with a greatly reduced strikeout rate.
Second-half callup is ... likely.

Also considered: Seth Beer, OF, HOU; Will Benson, OF, CLE; Vidal Brujan, 2B, TB; Dylan Carlson, OF, STL; Yusniel Diaz, OF, BAL; Jarren Duran, OF, BOS; Alex Faedo, SP, DET; Nolan Gorman, 3B, STL; Brusdar Graterol, SP, MIN; Trent Grisham, OF, MIL; Jordan Groshans, SS, TOR; D.L. Hall, SP, BAL; Ke'Bryan Hayes, 3B, PIT; Nico Hoerner, SS, CHC; Jonathan India, 3B, CIN; Nolan Jones, 3B, CLE; Nick Madrigal, 2B, CHW; Dustin May, SP, LAD; Triston McKenzie, SP, CLE; Ryan Mountcastle, 1B, BAL; Sean Murphy, C, OAK; Julio Rodriguez, OF, SEA; Brent Rooker, 1B, MIN; Keibert Ruiz, C, LAD; Jesus Sanchez, OF, TB