Following a season in which third-down efficiency was one of the San Francisco49ers' most glaring weaknesses, the coaching staff and QB Alex Smith made improving in that aspect a priority.

The team ranked 31st in the NFL by converting just 29.4 percent on third down in 2011 and was just 1 for 13 in a 20-17 OT loss to the Giants" data-canon="New York Jets" data-type="SPORTS_OBJECT_TEAM" id="shortcode0"> in the NFC Championship Game.

When Smith watched the game the next day, it marked the beginning of an offseason that included a lot of film study -- especially of third-down plays.

"In the offseason OTAs, you have just a huge catalog of everything," Smith said. "You’ve got every third down from the entire season, which is a lot of third downs. You get to look at how teams are playing us, what we’re doing, what we need to do better, things like that.”

The time spent studying film -- both with coaches and alone -- has offensive coordinator Greg Roman singing Smith's praises.

"He understands all the different things that we do and he’s really, really, really intelligent," Roman said. "He is super smart -- savant-like at times -- and has great ideas."

Smith has always been intelligent, so it's fair to question what could potentially make things different this season?

"As we studied [third downs] in the offseason and really throughout the season last year, it was really just a lack of execution, a lack of cohesion," Roman said. "I would attribute that to really just time on task, and I would fully expect our third-down production to be much better due to the fact that we’ve got a lot more time invested in it, and I think it’s that simple."

Roman's theory doesn't include the fact that Smith simply has more weapons on offense with the offseason additions of WRs Randy Moss and Mario Manningham and RBs Brandon Jacobs and LaMichael James.

Their arrival alone likely would have resulted in better third-down production, but with the offseason emphasis as well, it's clear the 49ers expect to improve significantly.

Dumervil and Miller present good challenge: Roman is looking forward to seeing how his team deals with Elvis Dumervil and Von Miller as pass rushers in the team's third preseason game Sunday at Denver. Both players ranked in the top 20 in the NFL in sacks last season.

"It will really be good work for us," Roman said. "I think just the way their defense is built right now with those two players coming off the edges, it’s tremendous work for us. We have to be on our A game.”

Boone still leads at RG: The coaching staff hasn't officially named Alex Boone the starter for the regular-season opener at Green Bay, but all signs point to that eventually happening.

"Alex Boone has done a very good job and continues to get better," Roman said.

Too little, too late for Dixon? RB Anthony Dixon's roster spot is jeopardy because of the team's depth at RB, but he is making a late charge at remaining with the team.

"I thought Anthony had one of his best games since I’ve been here [Saturday at Houston]," Roman said. "He needs to have another great one this week.”

Culliver out vs. Denver: CB Chris Culliver (knee) will not play Sunday at Denver.

Follow 49ers reporter Kyle Bonagura on Twitter: @CBSSportsNFLSF and @KyleBonagura.
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