RB Ryan Mathews was suppose to be an every down back this season, but the not-yet-risen star suffered a broken clavicle on his first carry of preseason on Thursday night vs. the Packers and will miss four to six weeks. The injury will undoubtedly have far reaching effects on how the 53-man roster is formed.

There has been some speculation that the Chargers will carry either four TEs or six WRs on the opening-day roster. Coach Norv Turner will now be forced to carry at least four RBs, which will limit his options elsewhere.

“I think anybody who thought that we wouldn’t carry four is naïve,” Turner said. “We are not going to go with three running backs. We have different scenarios when you make your team. With our group we could easily have five [RBs].”

With an extra RB it will be difficult to protect TE Ladarius Green (round four, 110th overall pick). Green had no receptions against the Packers, and he needs to improve as a blocker. Turner said after the draft he would consider carrying four TEs. The injury to Mathews may make that impossible.

Despite the loss of Mathews, there were several positives that came out of the 21-13 win. Most notably the pass rush looks to be dramatically improved. OLB Melvin Ingram (round one, 18th overall pick) and DE Kendall Reyes (round two, 49th overall pick) frequently helped collapse the pocket and get pressure on the QB.

Reyes finished the night with four combined tackles (one solo, three assists) and a half sack. Ingram had two solo tackles and one QB hit.

“[Ingram] brings a physical presence,” Turner said. “It showed up at a high level when you put the pads on.”

Three players who improved their stock

RB Curtis Brinkley: Brinkley was the game’s leading rusher with 11 carries for 42 yards and a TD. He came into the game on the bubble with many predicting he wouldn't make the final cut, but with the injury to Mathews he is now a virtual lock to make the opening-day roster.

WR Vincent Brown: Brown led all receivers with four receptions for 81 yards and a TD. WR Robert Meachem is expected to be the opening-day starter, but Brown has consistently shown that he is a playmaker who isn't afraid to fight for the ball. Brown may challenge Meachem for the starting job.

WR-KR Micheal Spurlock: Spurlock had three receptions for 52 yards and a long of 26 yards. Spurlock is projected by some to be the third WR, but the injury to Mathews may prevent a sixth WR. Spurlock’s performance, however, puts pressure on WR Richard Goodman, who didn't play.

Three players who hurt their stock

K Nick Novak: Novak hit the left upright on a 35-yard field goal attempt. Novak is competing with K Nate Kaeding to retain the kicking job after Kaeding tore his ACL in Week 1 last season. Kaeding was already a front-runner to return, so the miss greatly hurt Novak’s

RBs Michael Hayes and Edwin Baker: Baker (round seven, 250th overall) and Hayes (undrafted, Houston) came into the night likely competing for a practice squad spot, but with the injury to Mathews they now could be fighting for a spot on the 53-man roster.  Hayes had six carries for only 10 yards and a fumble. Baker had just one carry for three yards. Both will need to make more of their future opportunities.

What's next: The players will have Friday off and resume training-camp practices on Saturday.

Follow Chargers reporter Dan McLellan on Twitter @CBSSportsNFLSD and @sandiegosports.