We've already looked at the top five quarterbackscornerbacksrunning backslinebackerstight endssafeties, defensive linemen and kick returners in the Pac-12. We continue our series with a look at the big uglies.

1. Khaled Holmes, USC C

If you watched a lot of USC football last year, you may have noticed that quarterback Matt Barkley’s jersey was clean after almost every game. Thanks to the stellar play of the Trojan offensive line, Barkley was only sacked eight times all last season. With left tackle Matt Kalil now in the NFL, center Khaled Holmes is now the undisputed leader of USC’s offensive line. Coach Lane Kiffin complained about his running back depth at Pac-12 media day, however, with this line, it might not matter who’s in the backfield.

2. Carson York, Oregon, G

York anchored an Oregon line last year that allowed the Duck offense to flourish. Oregon was fourth in the country in both offensive yards per game (522.8) and yards per play (7.2). York’s easily the most experienced player on the line, having started in 36 of the 40 games he’s played in since 2009. York missed spring practice after having January surgery on his patellar tendon, but he’s expected to be ready for fall camp. If for some reason York’s not healthy enough to go, it would be a huge loss for Oregon’s O-line.

3. David Bakhtiari, Colorado OT

You might be scratching your head and saying to yourself right now, “Wasn’t Colordado 11th in the Pac-12 in total offense last season, how is there a Buffalo on this list?” The answer to that is simple: Bakhtiari is good. Despite the offense putting up poor numbers in 2011, Bakhtiari still played well enough to earn second team All-Pac-12 honors last season. In two seasons as a starter, Bakhtiari has only surrendered three sacks.

4. David Yankey, Stanford G

With Jonathan Martin and David DeCastro now in the NFL, the pressure falls on left guard David Yankey to become the leader of the Cardinal line. Coach David Shaw loves to run the ball – Stanford was second in rushing in the Pac-12 last year – so Yankey and the O-line will have to be physical with opponents starting in week 1 against San Jose State.

5. Matt Summers-Gavin, Cal OT

When southpaw quarterback Zach Maynard won the Bears QB competition following spring 2011, coach Jeff Tedford could have moved All-Pac-12 lineman and current Cleveland Brown Mitchell Schwartz to right tackle to protect Maynard’s blindside. Instead, Tedford kept Summers-Gavin at right tackle and the gamble paid off. Maynard had a solid season (2,990 yards, 17 TD) and the Bears rushed for over 2,000 yards as a team. The pundits have noticed Summers-Gavin too, as he’s been named a preseason third team All-American by Phil Steele and preseason first team All-Pac-12 by Blue Ribbon. 

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