While LG Daryn Colledge started 13 games at left guard last season, and started in 60 games over the past 4 seasons, the Green Bay Packers didn't show a lot of faith in their incumbent left guard by giving him only a 2nd round tender. By not giving him the highest tender it showed some willingness to trade him. Colledge will enter training camp penciled in as the starting left guard, but there could be a lot of competition for his job. There are more possibilities then just these three players, but they are the most likely candidates:
Daryn Colledge. As much as I complained about him last season, Pro Football Focus gave him a solid ranking for 2009 as the No. 19th guard overall. I'm willing to admit that a lot of the problems I saw from him last season were during his disastrous Week 2 through Week 4 stint as the starting left tackle, and that he usually held his own at left guard. Either way, this is still a position where the team could improve.
Jason Spitz. While he's rarely played left guard during his NFL career, his old starting job at right guard was taken over by RG Josh Sitton who seems certain to return to it in 2010 after a very good 2009 season. It's more likely he takes over at center (that's for another post) but if he loses out to C Scott Wells then he could find himself challenging Colledge. Spitz is returning from the same back surgery that DE Justin Harrell had to remove a herniated disk. Despite that bad comparison, he should back at full strength in 2010. The coaches seem to love him, and I wouldn't be surprised to see them make sure he has a starting job somewhere on the line.
T.J. Lang. He played exclusively at tackle last season (as far as I remember) but Mike McCarthy was quoted as saying that Lang is a "natural left guard." He can always backup at tackle while starting at guard, and either way the top backup tackle should be LT Bryan Bulaga. This is probably his best opportunity to win a starting job in 2010.