SANTA CLARA, Calif. (AP) -- A little-known offensive lineman with less than one full game of NFL experience could find himself starting for San Francisco in its biggest game of the year yet.
Every Sunday, Joe Looney goes through his own pregame practice on the Candlestick Park field well before his 49ers teammates on the active roster do it for real. Such is life on the practice squad, or development squad as it is called around here.
Forced into his first regular action at right guard early in Sunday's 23-13 victory against St. Louis when left tackle Joe Staley went down and Alex Boone shifted to replace him, Looney impressed his teammates and coaches with how quickly he settled into his position.
''It's helping the team out any way I can,'' Looney said. ''I know those guys are relying on me and I'm relying on the guys. It's a team game. You just always have to be ready. It (stinks) to see Joe Staley go down, a Pro Bowler.''
Looney began this week working at right guard with the first-team offense given that Staley's status for Sunday's game against Seattle (11-1) remains unclear as he nurses a right knee injury.
Coach Jim Harbaugh said Wednesday he wouldn't rule out Staley or left guard Mike Iupati, who has missed the past two games with a sprained left knee. Neither practiced Wednesday.
So, just who is Joe Looney? Many around the league might be asking that very question this week - and it's an obvious one. Especially considering Looney only made his NFL debut for three plays in the waning moments of the 49ers' Nov. 25 Monday night win at Washington before being called upon in a much more important situation Sunday.
Staley went down at the 11:13 mark of the first quarter against the Rams and didn't return.
''Joe (Looney) did an amazing job to come in, perform the way he did,'' quarterback Colin Kaepernick said Wednesday. ''He pretty much locked their front down the whole game. So, hats off to him.''
In fact, several of Looney's teammates have credited him for carrying himself in a way that made it tough to tell he had never done this before at the NFL level. That's what center Jonathan Goodwin shared with offensive line coach Mike Solari.
''You never really know what to expect with a guy who hasn't played,'' Goodwin said. ''One thing about him, he works hard and he's a student of the game. The one thing I told Coach Solari that I felt from the moment he came in the game Sunday was you got a confident vibe from him. His first real action for him to be in that position and for him to come in and be that way that says a lot about him.''
The 49ers selected the 23-year-old Looney in the fourth round of the 2012 draft out of Wake Forest. Little did they know he would break into a veteran, close-knit offensive line in December with a playoff berth at stake as an emergency fill-in.
Looney and the other young O-linemen who aren't usually on the game-day 53-man roster are among the first on the field to go through their own routine to stay ready.
''He's on it. He prepares very diligently,'' offensive coordinator Greg Roman said. ''He's a very professional, intelligent young man. Love his aggressiveness, too. He went after people, which is what we like. Without question he played really well. He was just genuinely excited to be out there and have an opportunity to play, and it showed in his performance. We had confidence in him, but it's his first time out there doing it and he stepped up big. We're very pleased.''
Enough so that he could get another shot Sunday against the NFC West-leading Seahawks, who already clinched their playoff berth and could capture the division crown with a road win at San Francisco?
That is still to be determined. Harbaugh is never one to offer his opponent any kind of lead time, and especially not Pete Carroll and the archrival Seahawks.
Whatever happens, Looney earned the respect of his teammates.
''He just did a great job throughout the whole game,'' fullback Bruce Miller said. ''There was no fall off, no drop off with Joe (Staley) leaving. I'm really impressed with the way he handled himself. He's confident, and very humble in his approach. He prepares like a starter, so when he goes in there, he's a starter.''
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