Poll: Toughest Pac-12 player to replace?

The reality of college football is that all players eventually leave and the best players often leave sooner -- for the NFL draft -- than fans and coaches would want.

So while many view a count of returning starters as a great measure of what things might look like in the future, filling voids is really what spring practices are all about.

Many key conference players are off to the NFL. But which leaves behind the biggest hole?

For four years, Jake Locker was the face of Washington. While his numbers weren't good in 2010, he was the Huskies unquestioned leader, not to mention being good enough to go eighth overall in the NFL draft.

Just like Locker, Jacquizz Rodgers was the face of Oregon State, starting with his thrilling debut in the 2008 upset of USC. Speaking of difficult to replace, what about one player who was two players? That was Stanford's Owen Marecic in 2010, who was the Cardinal's starting fullback and linebacker.

Oregon is replacing three starters on its defensive line, but none was as productive over the past two seasons as end Kenny Rowe, who produced 20 sacks and 31.5 tackles for a loss over the past two seasons.