With three preseason games remaining, time is of the essence for those Packers players who have a chance of winning a spot on the team's 53-man roster.

A good performance in the remaining exhibition games, along with impressive work during training camp practices, can go a long way toward earning a roster berth. Likewise, a poor showing can mean doom for a player's roster life.

The following players are among those who still have a lot riding on their performance the rest of the preseason and whose futures are not determined one way or the other.

This article assumes no serious injuries will occur between now and the end of training camp. A door can be open in a heartbeat for those listed in the "out" category if an injury were to occur. By the same token, just because a player is listed as "out," doesn't mean they may not stick around on the practice squad.

Quarterbacks

Locks: Aaron Rodgers

Graham Harrell––In his fourth season, Harrell knows the Packers offense. Now he's got to start putting the entire package together. It's necessary for Harrell to start completing some downfield passes, or the team will find someone that can.

Vince Young––Young only gets the benefit of the doubt for so long. He has to prove capable in a game setting if the Packers are going to invest a roster spot into Young for the long term.

Out: B.J. Coleman

Running Back

Locks: Eddie Lacy, DuJuan Harris, Johnathan Franklin

James Starks––Based on his play early in training camp, Starks is ahead of Alex Green for a final roster berth at running back. The key will be for Starks to continue his string of solid play, and perhaps even more importantly, stay healthy.

Alex Green––Green needs to have good preseason performances because he's not only auditioning for the Packers, he's auditioning for every team in the NFL. Unfortunately, he just hasn't shown the same explosion as he had pre-surgery following an ACL tear in 2011.

John Kuhn––It is with great trepidation Kuhn is listed as being on the roster bubble. His obvious worth is as a pass protector for Aaron Rodgers. If it's third and long and the Packers absolutely know they're going to throw the football, who else would you rather have lining up next to Rodgers in the backfield?

Out: Angelo Pease, Jonathan Amosa

Wide Receivers

Locks: Jordy Nelson, Randall Cobb, James Jones, Jarrett Boykin

Jeremy Ross––It only helps Ross's cause that Cobb has a lingering biceps issue. He's the front-runner to take over return duties from Cobb and become a fifth or sixth option at wide receiver, but he must show consistency with his ball security in catching kicks, punts and passes. Muffs, fumbles and drops can simply not be tolerated.

Tyrone Walker––Walker has impressed, going so far seeing playing time with the first-string offense in the absence of Nelson and Cobb. The question is, is there room to keep a fifth or sixth wide receiver that doesn't figure to be active on game days during the regular season assuming all the other receivers are healthy?

Out: Charles Johnson, Kevin Dorsey, Myles White, Alex Gillett, Omarius Hines, Justin Wilson

Tight Ends

Locks: Jermichael Finley, Matthew Mulligan

D.J. Williams––Williams' game against the Cardinals in Week 1 of the preseason basically defined his career thus far in a nutshell. He followed up a beautiful fingertip catch with two drops. He has to be more consistent in both his receiving and his blocking if he's going to stick another season in Green Bay.

Andrew Quarless––Quarless hasn't played since December of 2011. Time is running out for the player who suffered a gruesome knee injury. He has to get back out on the field and prove that he's healthy. One option available to Quarless is to stick around as the one player designated for return on injured reserve if his current quad injury lingers.

Ryan Taylor––Taylor returned from his recent knee injury not a moment too late. Like Quarless, he needs to be on the field to prove his worth. Special teams alone will not be enough for Taylor to stick around. He needs to show he can play on offense too.

Brandon Bostick––The only way Bostick can make the roster is if he starts making some nice downfield catches and does good things with the ball in his hands. He may have potential, but he has yet to show it in a professional game environment.

Out: Jake Stoneburner

Offensive Line

Locks: David Bakhtiari, Josh Sitton, Evan Dietrich-Smith, T.J. Lang, Don Barclay, Marshall Newhouse, Greg Van Roten, Bryan Bulaga (IR), J.C. Tretter (PUP)

Lane Taylor––Taylor graded out the highest of any player on the Packers offense in the team's first preseason game, according to ProFootballFocus.com. But is there room on the team's roster for a player who appears to be strictly a guard, at least at this point in his development?

Derek Sherrod––If Sherrod were to be cleared to return, he might have a chance at winning a backup tackle job. But as it stands, it appears the Packers will have to choose between cutting Sherrod outright, or having him start the season on the PUP list.

Out: Andrew Datko, Patrick Lewis, Garth Gerhart, Kevin Hughes

Defensive Line

Locks: B.J. Raji, Datone Jones, Ryan Pickett, C.J. Wilson, Mike Neal, Mike Daniels, Jerel Worthy (PUP)

Johnny Jolly––It appears as if six defensive linemen are locks on the Packers' roster and a potential seventh spot will come down to a choice between Jolly and Josh Boyd. Jolly has the edge in experience. He's had an impressive camp so far, but Jolly can't afford to regress whatsoever.

Josh Boyd––Working in Boyd's favor over Jolly is that he's younger and on a four-year contract. Jolly's contract is up after this season. If things don't work out, there would appear to be a spot on the team's practice squad for Boyd if nothing else.

Out: Jordan Miller, Gilbert Pena

Outside Linebackers

Locks: Clay Matthews, Nick Perry, Dezman Moses

Andy Mulumba––The good news for Mulumba is that he's actually been working ahead of Palmer in the outside linebacker rotation so far in training camp. The bad news is that he hasn't done anything outstanding yet. He's been solid but not spectacular.

Nate Palmer––As a sixth round draft choice, you don't want to give up on Palmer too early, but he clearly hasn't done much of anything so far in his brief Packers career. A couple sacks in preseason action could change that.

Out: Donte Savage, Jarvis Reed

Inside Linebackers

Locks: A.J. Hawk, Brad Jones, Robert Francois, Jamari Lattimore, Terrell Manning, Sam Barrington

It's hard to see the Packers parting ways any of the six inside linebackers on the roster. While the four backups beyond Hawk and Jones may not see a lot of regular season playing time, they'll comprise the core of the team's special teams units.

Out: None

Cornerbacks

Locks: Tramon Williams, Casey Hayward, Sam Shields, Davon House, Micah Hyde, Jarrett Bush

The injuries to Williams and Hayward could open a door for another cornerback if their ailments continue to linger. But unless that happens, the Packers would appear to be set with a group of six cornerbacks on their regular-season roster.

Out: James Nixon, Loyce Means, Brandon Smith

Safety

Locks: Morgan Burnett, Jerron McMillian, M.D. Jennings

Sean Richardson––Obviously Richardson needs to become cleared for action to earn a spot on the team's roster. But he might be the only player capable of earning the fourth safety spot. While Fulton and Banjo might be good candidates for the practice squad, it's difficult to see either of them making the 53-man roster. The Packers may need to look to the waiver wire to find another safety.

Out: David Fulton, Chris Banjo, Chaz Powell

Special Teams

Locks: Tim Masthay, Brett Goode

Mason Crosby––It's absolutely necessary for Crosby to have  solid showing in the remaining preseason games. He's already on shaky ground, and the Packers can't afford to allow him to work through his struggles for much longer.

Giorgio Tavecchio––Tavecchio is competing with Crosby and every other kicker in training camps across the NFL. He has to impress or the Packers may not be afraid to pick up another team's castoff.

Brian Carriveau is the author of the book "It's Just a Game: Big League Drama in Small Town America," and editor of Cheesehead TV's "Pro Football Draft Preview." To contact Brian, email [email protected].