Alex Reyes is one of those exciting young talents who tests the limits of what it means to be a prospect. 

Technically, he exhausted his rookie eligibility earlier this season, which would make him ineligible for most traditional prospect lists. Technically, he's on a rehab assignment, working his way back from a broken finger, which isn't the same as toiling away in the minors.

Because of these technicalities, I'm less than motivated to include him in my Five on the Verge, but it doesn't mean I'm less than enthusiastic about stashing him. The reason he figures to spend time at Triple-A once his rehab is done is because the Cardinals are stretching him out to start again, and he's their rotation's best hope following Michael Wacha's demotion to the bullpen.

His stuff, as anyone reading this column surely knows by now, is off the charts, with a fastball that rates at the top of the scale as well as a plus curveball and changeup. Injuries have held him back — he tore a lat muscle in his first start back from Tommy John surgery last year — and may explain the lapses in command early this season. His is the sort of talent you'll want to scoop up ahead of time, though, because as soon as we learn he has a rotation spot again, which seems to be the direction the Cardinals are headed, it'll be a race to see who grabs him first. The need at the position is too glaring for Fantasy players to take a wait-and-see approach.

To that point, it's worth noting Jon Duplantier may be on the verge of making his first major-league start with Luke Weaver now sidelined by a strained forearm. Duplantier made five relief appearances, including three of three innings or more, earlier this year, and it went well enough. He does, however, have a 4.76 ERA in six starts at Triple-A this year, having issued 13 walks in 17 innings.

He made a name for himself with a 1.39 ERA and well more than a strikeout per inning in the lower minors two years ago but has lost footing since then and is on the fringes of most top 100 lists. I'd prefer to take more of a wait-and-see approach with him given the recent inconsistencies regarding usage and performance, so even though he may have a clearer path, I'm still placing him just outside of my ...

Five on the verge

(These are the prospects most worth stashing in redraft leagues.)

Yordan Alvarez, OF, Astros

2018 minors: .293 BA (335 AB), 20 HR, 21 2B, .904 OPS, 42 BB, 92 K
2019 minors: .367 BA (188 AB), 20 HR, 16 2B, 1.221 OPS, 28 BB, 40 K

True, Alvarez didn't get the call when George Springer first went on the IL with a Grade 2 hamstring strain — an injury that will likely sideline him for several weeks — but since then, the Astros have learned they'll be without Carlos Correa for 4-6 weeks because of a broken rib. Alvarez doesn't play shortstop, of course, but one of the most cited reasons for why they're in no rush to bring him up is because their offense is performing well enough without him. Take away three of their best hitters (Jose Altuve is also sidelined for several more weeks), and the argument no longer holds water. Plus, Correa's absence shifts Alex Bregman over to shortstop, which shifts Yuli Gurriel over to third base, which frees up first base — i.e., Alvarez's natural position.

Kyle Tucker, OF, Astros

2018 minors: .332 BA (407 AB), 24 HR, 20 SB, .989 OPS, 48 BB, 84 K
2019 minors: .261 BA (184 AB), 16 HR, 10 SB, .941 OPS, 21 BB, 44 K  

Given how completely Tucker has turned his season around — he's batting .351 with 14 homers, eight steals and a 1.275 OPS in his past 30 games, which are better numbers than Alvarez has in that same span — I'm beginning to think he might beat Alvarez to the majors this year, especially seeing as he's already on the 40-man roster. No, he wouldn't fit neatly at first base like Alvarez would, but right now, the Astros are forced to play Tyler White and Derek Fisher every day — not to mention Jake Marisnick, who has managed to hold it together so far but doesn't have a great track record offensively.

With no one committed to the DH spot full-time, there's an easy path for Tucker when the Astros decide they need more offense, which could be any day now. They haven't always let Super 2 concerns dictate the timeline for their top prospects, you know (see Springer, George). 

Zac Gallen, SP, Marlins

2018 minors: 8-9, 3.65 ERA, 1.47 WHIP, 133 1/3 IP, 48 BB, 136 K  
2019 minors: 7-1, 1.70 ERA, 0.68 WHIP, 74 IP, 13 BB, 88 K

Turns out the biggest prospect surprise of 2019 isn't ready to come back down to earth yet. Gallen followed up his one and only bad start back on May 19 with back-to-back one-run gems. Even in the bad start, he struck out 10 and walked one, so there's no sign of him losing traction here. Finding a more consistent arm slot this spring has helped him max out his command, which explains the leap in performance. And while Triple-A hitters aren't the same as major-leaguers, offensive production has gone crazy at that level (and especially the PCL) with the introduction of a new baseball. As soon as the Marlins have an opening in their rotation — they've managed to run the same five out there so far — Gallen is coming up.

Jesus Luzardo, SP, Athletics

2018 minors: 10-5, 2.88 ERA, 1.09 WHIP, 109 1/3 IP, 30 BB, 129 K  
2019 spring: 0-0, 0.93 ERA, 1.03 WHIP, 9 2/3 IP, 4 BB, 15 K

Luzardo indeed progressed from throwing bullpen sessions to facing live hitters this weekend and actually hit 96 mph in a live batting practice session Saturday. So maybe he won't need as much time to get back to game form as some had feared. All of June still seems likely, though, and once the calendar flips to July, it's easy enough to justify holding him out until after the All-Star break. So yes, we could point to other prospects with presumably shorter timetables than Luzardo, but the likelihood of him making an impact, particularly at a position of need, is high enough that I'm happy to stick with him. He was dominating this spring and, like Chris Paddack, could have forced his way into the starting rotation, but then he hurt his shoulder.

Luis Urias, 2B, Padres

2018 minors: .296 BA (450 AB), 8 HR, 30 2B, .845 OPS, 67 BB, 109 K
2019 minors: .364 BA (143 AB), 13 HR, 9 2B, 1.203 OPS, 23 BB, 30 K  

Hard to say exactly what the holdup is here, though some online have theorized that the Padres are trying to "buy back" a year of team control after already giving Urias about a month of service time. If that's indeed the goal, they should have just about achieved it by now, and since they appear well positioned to make a wild card run, upgrading from a .185-hitting 36-year-old (Ian Kinsler) would presumably be a top priority. Urias has always demonstrated impressive bat skills but has taken them to new heights this year, having already nearly doubled his career high in home runs while boasting the ninth-best batting average and third-best OPS in all the minors.

Five on the periphery

(These are some other prospects doing something of note.)

Brendan McKay, SP/1B, Rays

2018 minors: 5-2, 2.41 ERA, 0.88 WHIP, 78 1/3 IP, 14 BB, 103 K  
2019 minors: 4-0, 1.16 ERA, 0.79 WHIP, 46 2/3 IP, 9 BB, 66 K 

McKay's promotion to Triple-A last week was the clearest indication yet that the Rays aren't going to let his bat hold back his arm, which means this two-way hopeful may be on the verge of something much more conventional in the near future. There's nothing conventional about his numbers, though. Defined mostly by his outrageous strikeout-to-walk ratio, the left-hander continued his efficient ways in his Triple-A debut Tuesday, throwing just 65 pitches in five shutout innings. Because he threw less than 80 innings last year, his workload will be limited, but with the Rays in contention for the AL East crown, they may decide those innings are better spent in the majors.

Bobby Bradley, 1B, Indians

2018 minors: .224 BA (483 AB), 27 HR, 26 2B, .774 OPS, 56 BB, 148 K
2019 minors: .282 BA (177 AB), 14 HR, 14 2B, .954 OPS, 18 BB, 65 K  

Bradley first entered the prospect scene as a teenager — a rarity for a player whose defensive profile limits him to first base — but persistent contact issues lowered his stock as he climbed the minor-league ladder. Those issues are as acute as ever, but so is his greatest strength, hitting home runs, which he has now done six times in his past eight games. The Indians are flailing right now, with a lack of offense being their biggest problem, and since they don't have a dedicated DH and could fit in any hitter they so choose, it might be sink-or-swim time for one who's looking like he's too good for Triple-A.

Kyle Muller, SP, Braves

2018 minors: 11-3, 3.03 ERA, 1.23 WHIP, 139 2/3 IP, 46 BB, 129 K  
2019 minors: 3-1, 1.89 ERA, 1.20 WHIP, 52 1/3 IP, 32 BB, 57 K 

Just in case the Braves didn't have enough pitching prospects, their second-round pick from 2016 looks like he's turning the corner, having overcome an early-season bout with wildness to put together a 0.81 ERA with right at a strikeout per inning over his past five starts for Double-A Mississippi. Three of them were of the seven-inning variety and another was just an out shy. It isn't just the control that's improved, a product of him being more consistent with his delivery, but also his velocity, which now touches 97 mph after spending time this offseason working with Driveline Baseball, a data-driven development program that's gaining in popularity.

Jarred Kelenic, OF, Mariners

2018 minors: .286 BA (220 AB), 6 HR, 15 SB, .839 OPS, 26 BB, 50 K
2019 minors: .303 BA (188 AB), 10 HR, 7 SB, .955 OPS, 25 BB, 45 K     

The sixth overall pick in the 2018 draft and prize of the Edwin Diaz deal has so thoroughly impressed in his first year of full-season ball that he's already on the move up to high Class A. The power is coming along even quicker than expected for a player with both a polished approach at the plate and the athleticism to steal bases, so provided he doesn't stall at the upper levels, Kelenic may be one of those high school draft picks who's advanced enough to reach the majors by his 21st birthday. If nothing else, his performance this year has elevated his dynasty appeal from good to great.

Brian O'Grady, OF, Reds

2018 minors: .280 BA (322 AB), 14 HR, 9 SB, .871 OPS, 39 BB, 80 K
2019 minors: .331 BA (154 AB), 14 HR, 9 SB, 1.106 OPS, 20 BB, 53 K   

O'Grady has played almost exclusively first base this year but retains outfield eligibility in CBS Sports leagues from his previous years in the minors — which are many, seeing as he's already 27 years old. He's not overtaking Joey Votto at first base no matter how long the future Hall of Famer's slump persists, but O'Grady's newfound power (he has a three-homer game and two two-homer games in the past two weeks) was the missing piece in what has become an intriguing offensive profile over the past couple years. The Reds have a number of similarly intriguing pieces in their outfield already, which is why there's no reason to believe they're gearing up to add O'Grady to the mix until he begins seeing more reps out there. It's unlikely he makes a real Fantasy impact without some sort of injury to open the door.