SANTA CLARA, Calif. -- The San Francisco 49ers are trading places again along their offensive line, and even quarterback Shaun Hill admits that could be a good thing as the team emerges from its bye week.
Hill got banged around a bit too often, and San Francisco's power rushing attack never really got untracked in the first five games.
The offense did enough to help the 49ers to a 3-2 start and first place in the NFC West, but improvement is a must if San Francisco is to remain atop the division and end a string of six consecutive losing seasons. That improvement must start up front.
"Yeah, a tweak could be good for us, without a doubt," Hill said. "We have the right people in that locker room where we will make it work."
Tony Pashos will start at right tackle Sunday against the Texans in Houston. Pashos, who has 54 career starts at tackle with Baltimore and Jacksonville, joined the 49ers the week before this season began after being released by the Jaguars.
Pashos is taking over for Adam Snyder, who started the first five games at right tackle but now will move inside to share time with struggling right guard Chilo Rachal.
It's the first time this season the 49ers will have different starters on a line that experienced constant change and transition last year. The unit has yet to find the continuity and cohesion expected from it and has been a conspicuous problem area for an offense that ranks 29th in the NFL.
"If I had a concern that you have anxiety over at the start of a game, that would be it because that continuity is very delicate and takes time," said offensive coordinator Jimmy Raye.
Running back Frank Gore will return this week after missing the past two games because an ankle injury, and San Francisco also will get a boost from the arrival of touted first-round pick Michael Crabtree at wide receiver.
But those offensive weapons can't be effective unless the line is opening holes up front and protecting Hill, who has been sacked 16 times and is coming off his worst game as the team's starting quarterback. The 49ers rank 29th in the NFL in sacks allowed per play.
Hill has been sacked on 10.6 percent of his pass plays, and only the Green Bay Packers (12.7 percent) are allowing sacks at a more rapid rate.
"Any time the quarterback gets hit, it's too many," Snyder said. "We have to do a better job in protection and in the run game."
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The 49ers have the league's lowest rating on so-called power runs, which are described as running plays on third or fourth down with two or fewer yards to go. San Francisco has converted 43 percent of its power runs. The NFL average is 63 percent.
Snyder gives the 49ers more size and experience inside over Rachal, who took over as the starting right guard last year as a rookie but has been the culprit in blown assignments this year due to his aggressive style.
Snyder has started at every position along San Francisco's line but center, with four of his 43 career starts coming at right guard.
The 49ers have not yet determined who will start at right guard, but said Snyder and Rachal both will see action at the position on a rotating basis.
"It's a tag team, basically," Rachal said. "It's still a learning experience for me and I can learn from Adam. We've been physical as a line and we're hungry and working hard. We just have to do better."
Copyright 2009 by The Associated Press