SANTA CLARA, Calif. -- San Francisco 49ers coach Jim Harbaugh wouldn't say whether the team's offensive line, which until recently has been a model of durability, will be without two integral components in a pivotal game Sunday against visiting Seattle.
However, neither player practiced Wednesday. Both were seen working on elliptical machines during the beginning stages of practices.
Staley suffered a sprained MCL in his right knee Sunday against St. Louis. Iupati has missed the past two games with the same injury, although his is considered more severe. Staley was walking without much of a limp Wednesday.
Treatment throughout the week will determine whether Staley and Iupati can play. If not, right guard Alex Boone will play left tackle and young Joe Looney will play at right guard while Adam Snyder remains at Iupati's spot. That was the alignment the 49ers used after Staley was injured early Sunday.
Harbaugh praised the play of the entire group in a difficult situation against a Rams front four that is considered one of the NFL's finest.
Until Iupati went down Nov. 17 at New Orleans, the 49ers had started the same five offensive lineman since the start of the 2012 season. As the 49ers adjust to the injuries, quarterback Colin Kaepernick praised Looney's play, his first extensive NFL work.
"Joe did an amazing job to come in, perform the way he did," Kaepernick said Wednesday. "He pretty much locked their front down the whole game. So, hats off to him."