Welcome to the fourth annual best and worst case scenarios for every player on the Green Bay Packers roster.

I attempt to take a look at what is the very best possible season a player is capable of producing, and on the other hand, what would happen if a player fell flat on his face (without assuming they suffer a season-ending injury). These are intended to be extreme scenarios on both sides of the spectrum. More than likely, each player is going to fall somewhere in the middle, but every now and then, they just so happen to come to fruition. Think Charles Woodson last year.

I also try to take a look at what these scenarios would be from an individual standpoint and not what’s best for the team. For example, parting ways with Justin Harrell may eventually be what’s in the best interest of the Packers. I’m more interested in looking at what’s in Justin Harrell’s best interests (or worst interests for that matter).

Yesterday we looked at the quarterbacks. Today we look at the running backs ...

Ryan Grant

• Best-case scenario: The accolades finally come with the gaudy statistics Grant always seems to put up. Grant has put up an increasing number of yards every year he's been in the league from 956 in 2007 to 1,203 in 2008 to 1,253 in 2009. With a good passing game to take pressure off the running game, Grant ups the ante once again with over 1,300 yards and double digit touchdowns. And he finally gets that elusive Pro Bowl nod that's been missing ever since he entered the league. Looks like the offseason training doing MMA has paid off as Grant's flexibility has improved and he's better getting both to and beyond the second level.
• Worst-case scenario: Heading into his fourth season being the primary ball carrier by a large margin finally takes it's toll. For one, there's no one to split carries with as a change of pace or to give him a breather. On top of that, injuries start to pile up as the wear and tear catches up to Grant. The old adage that running backs only have a certain number of carries creeps  into observers' consciousness. Grant's production drops dramatically, and it becomes clear that Grant can no longer be the Packers' only ball carrier.

Brandon Jackson

• Best-case scenario: This is the year Jackson puts everything together. Who knows why it took so long, but it all seems to click. Jackson rules the third-down back role. He becomes the team's biggest receiving threat out of the backfield, but he also starts stealing away carries from Ryan Grant as well. Jackson has somewhere in the neighborhood of 500 yards and leads the team in average yards per carry. As expected, he maintains his status as a great pass blocker.
• Worst-case scenario: Jackson is passed up in the pecking order by rookie James Starks. By the end of the year, Jackson barely plays, and it's pretty much a forgone conclusion that he won't be a Packer in 2011. He plays occasionally on third downs, but by the end of the year he only has somewhere between 30 to 40 carries the entire season. He's basically a non-factor and is only kept around because he was a high-round draft choice in the not so distant past.

James Starks

• Best-case scenario: In the second half of the season, Starks becomes the perfect complement to Ryan Grant. He seems to improve each and every week. He may exhibit the typical rookie learning curve, but he shows flashes of potential in the preseason. He makes the most of his limited opportunities in the early portion of the regular season, and by November, it's clear that he needs to be on the field. He finished with over 300 yards for the season, contributes a couple of touchdowns and his future looks bright.
• Worst-case scenario: Starks can't seem to find the field. Not unlike Quinn Johnson a year ago, he's kept around on potential alone, but he's not ready for primetime. He gets a carry here or there, but he just can't be trusted yet. He has mental errors, he has problems running with an upright running style he just can't seem to change and he gets no more than a carry or two a game at most. He's frequently on the inactive as the result of the mandatory 45-man gameday roster.

Kregg Lumpkin

• Best-case scenario: Thanks to a Superman-like effort in training camp, Lumpkin finds his way onto the team. He leads the time in rushing in the exhibition season, but most impressive is his ability to find the endzone. Even if the Packers have to keep four halfbacks on the roster, they decide they can't afford to let Lumpkin go. He doesn't have a major impact in the regular season, but he sees maybe five carries a game and becomes part of the conversation.
• Worst-case scenario: When he does nothing to distinguish himself from the other running backs on the roster during training camp, he's cut before the regular season begins. He gets ample opportunities in preseason games but fares worse than Brandon Jackson and James Starks. There's no reason to keep him around, and his best best chance to get a job in the NFL is somewhere other than Green Bay.

Quinn Porter

• Best-case scenario: Porter is stashed on the 53-man roster pretty much for the sole reason that he provides a spark as a kick returner. Once training camp rolls around, he shows why he averaged over 30 yards a kick return in college. He rarely if ever sees the field on offense, but just by making the team, he already exceeded all expectations.
• Worst-case scenario: Being the second- or third-string kick returner isn't enough to warrant a roster spot let alone a job on the practice squad. Porter isn't any better than guys like Will Blackmon, Sam Shield, Jordy Nelson, James Starks, or pretty much anyone on kick returns. His impact at running back is nil, and he doesn't make it beyond the first round of roster cuts.

John Kuhn

• Best-case scenario: Kuhn shows to be the most well-rounded of all the fullbacks. He can block, he can catch, he can play on special teams and even though he isn't going to wow anyone with his ball carrying capabilities, he at least has experience in that area. He has a stranglehold on the starting fullback job he just doesn't let go. He hangs onto that job, and is praised for his lead blocking for Ryan Grant when the tailback is actually able to break off some long runs this season.
• Worst-case scenario: Kuhn isn't as good a blocker as Quinn Johnson and he's not as good a receiver or special teams player as Korey Hall. As such, Kuhn becomes expendable. The Packers can't afford to keep three fullbacks on the roster this year, and Kuhn is cut when the Packers are forced to make a decision in early September. At least he'll be known as a high-character guy, and hopefully he'll find a job elsewhere in the NFL. The Bengals had shown interest in him in the past.

Korey Hall

• Best-case scenario: Korey Hall isn't the most glamorous player on the team, but he's an overlooked contributor thanks to the work he does both on offense and on special teams. He splits time on offense with whoever the other fullback is, but he does adequately whenever he plays. He's a decent receiver out of the backfield and adds a touchdown or two in 2010. He's underrated on special teams and is actually one of the best players on the team in that category.
• Worst-case scenario: If you're going to be a fullback in the NFL, you better be able to block. And because he's a little bit behind both Kuhn and Johnson, the Packers can't afford to keep Hall going forward. He was good on special teams, but he nothing that couldn't be replaced by either of the other two fullbacks on the team. Flat out, he didn't do enough to warrant a roster spot at a position that's becoming extinct in today's NFL.

Quinn Johnson

• Best-case scenario: Look out. The Packers make a decision to make Johnson the starting fullback Week 1 and never look back. He becomes a punishing blocker and starts becoming known as one of the best in the NFL among the inner circles. Unfortunately, any accolades that come with being the best at your position are years away, but it doesn't matter to the Packers. Johnson helps them have one of their best rushing attacks in years. He becomes assignment sure and is capable enough when he touches the football.
• Worst-case scenario: He makes the team once again but doesn't really impress. His sophomore season in the NFL basically mirrors his rookie year. He plays from time to time, he starts to have an expanded role on special teams, but he just never seems to take it to the next level. Either Kuhn or Hall are more reliable or just seem like better options whenever the Packers need a fullback. Time's running out if he's going to continue to make a career out of playing football.