There's always a moment in an NFL career when the time comes to stand tall and deliver -- or disappear, maybe for good.
It's tough for players to face that crossroads as a rookie, but for some draftees, that's just how it is depending on their situation. Make no mistake, when they call your number it's time to go!
Here are 16 players in the crucible this season. Their teams have put the onus on them to succeed, and if they don't come through, their teams will likely disappoint.
Jason La Canfora blog
Donovan McNabb's shadow still looms large over the Philadelphia Eagles, and it won't be easy for Kevin Kolb to live up to his wildly successful predecessor, Vic Carucci says. **More ...**
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1. Kevin Kolb, QB, Philadelphia -- Kolb replaces Donovan McNabb, who moved down I-95 to Washington and is positioned to haunt the Eagles and Kolb. Philadelphia is a rough town and any sign of weakness will be pounced on by the fans and media. In two career starts, Kolb has completed 55 of 85 passes for four touchdowns, seven interceptions and five sacks. His tendency to throw interceptions (he threw one every 12 pass attempts) is the first issue he has to correct.
2. Matt Leinart, QB, Arizona -- The former first round pick finally takes over the team he was supposed to lead four years ago. Leinart has good experience with 595 pass attempts under his belt, but his 14 touchdowns to 20 interceptions ratio has to improve. He's also been sacked way too much -- 29 times. The Cardinals have been working towards developing a better running game, and it needs to be there in time for Leinart's debut as the true starter.
3. Byron Leftwich, QB, Pittsburgh -- Granted, it's a temporary position, but it could last six games, and unless he delivers, the Steelers' season could be over before suspended quarterback Ben Roethlisberger returns. Leftwich has started five games in the last three years and has been sacked 11 times, while attempting only 201 passes -- a poor ratio.
4. Dwayne Jarrett, WR, Carolina -- The Panthers have been patient with Jarrett, but he's only managed three starts, 33 receptions and one touchdown in three seasons. Muhsin Muhammed retired, Steve Smith broke his arm and inexperienced Matt Moore takes over at QB, making Jarrett's contributions all the more important.
5. Doug Free, LT, Dallas -- The Cowboys let Flozell Adams go for financial reasons and handed the left tackle spot to Free. He has seven career starts and must protect Tony Romo in an offense that featured 34.4 pass atempts per game last year. It's a big gamble in a division that includes elite pass rushers like the Redskins' Andre Carter, the Eagles' Trent Cole and the Giants' Osi Umenyiora.
7. Robert Ayers, OLB, Denver -- This former first-round pick looked like Vernon Gholston did for the Jets as a rookie. No sacks in 15 games. The Broncos' 3-4 defense is not going to work unless Ayers delivers as an outside linebacker. He was running with the second team during minicamp, which isn't a good sign.
8. Brad Jones, OLB, Green Bay -- He replaced Aaron Kampman last year when Kampman went down with an injury. Clay Matthews came through big time on the other side with 10 sacks, but Jones only had four. He looks capable of a big season, and the Packers will need it if they want to take down the Vikings and hold off the Bears.
9. Jonathan Goff, MLB, New York Giants -- Ever since Antonio Pierce went down with a neck injury in Week 9 last season, the middle linebacker spot on the Giants has been an issue. They didn't sign a free agent middle linebacker, or draft one until the fourth round. That means the responsibility falls squarely on Jonathan Goff. He has four career starts in two years with 18 tackles, one pass defended and one sack in those games. The Giants are solid playoff contenders, but need a big year from Goff.
10. Kareem Jackson, CB, Houston -- It may be too much to ask of a rookie corner to come in and replace Dunta Robinson, who left for Atlanta in the offseason. The Texans are going nowhere if they can't stop division foe Indianapolis and that means stopping Peyton Manning. Manning has beaten the Texans six straight times, completing 164 of 229 passes and 12 touchdowns over that span. You can bank on Manning going after the rookie.
11. Ogemdi Nwagbuo, NT, San Diego -- The former Michigan State player filled in for Jamal Williams on the nose last year for five games as a rookie, and did well. It will get tougher starting 16 games, however. Defensive coordinator Ron Rivera will scheme the defense to protect him, but in the end Nwagbuo has to stand up to the pressure and deliver like Williams did for years.
12. James Hardy, WR, Buffalo -- Terrell Owens was not re-signed and someone has to replace his 55 receptions and five touchdowns from last year. Hardy was a bit raw coming out of Indiana and he only has three career starts in two years with just 10 receptions. He faces a tall order on a team that may be playing catch-up for most of the season.
13. Matt Slauson, G, New York Jets -- Alan Faneca may have lost a step as a Hall of Fame guard, but many feel he didn't lose enough to be replaced by a guy without a single NFL start. The Jets have a team that made it to the AFC championship Game last year and are betting on an inexperienced left guard.
14. Charlie Anderson/Koa Misi, OLBs, Miami -- Gone are Joey Porter and Jason Taylor and their 2009 production (16 sacks, four forced fumbles). Anderson is in his seventh year with just eight career starts, and Misi is a rookie.
15. Lamarr Houston, DE, Oakland -- Houston is a fine prospect, but he has tough shoes to fill in replacing Greg Ellis, who had 29 tackles, seven sacks and two forced fumbles. The Raiders are making a push to emerge from their losing wats and needs Houston to deliver now.
16. Ryan Mathews, RB, San Diego -- Mathews wore LaDainian Tomlinson's number all throughout high school and now takes over for him in the Charger backfield. It is possible he will carry the ball close to 250 times. Knowshon Moreno of the Broncos had 247 carries as a rookie last year. The Chargers are the favorites once again in the AFC West and a lot is expected of Mathews.