Seahawks receivers Ben Obomanu, Mike Williams both listed as questionable for game Sunday at San Francisco

RENTON — The anatomy of Seattle's passing game Sunday in San Francisco will come down to two game-time decisions, one regarding the left ankle of split end Mike Williams and the other on the injured hand of flanker Ben Obomanu.

Neither receiver practiced Friday and both are listed as questionable, which means the Seahawks estimate a 50 percent chance of playing.

Coach Pete Carroll said both will be evaluated Sunday, but it sounds like Obomanu is likely to be available after suffering a severe cut on his right hand during last week's victory over Carolina.

"I think he's going to play," Carroll said.

Obomanu is in his fifth year with Seattle and started the first game of his career four weeks ago in Arizona. He has caught 16 passes the past four games and scored two touchdowns. He suffered an ugly laceration when he was hit after a second-quarter reception last week. The cut required extensive stitches, and he has been outfitted with a protective device.

"He's got stitches in his hand," Carroll said. "They're going to be there on game day. We've just got to see how it works for him and how the little device that they're putting on his hand works out for him. They've been experimenting all week and everybody feels good about it."

Obomanu did not catch any passes this week in order to give the cut as much time as possible to heal, but he has been able to run and do conditioning drills. Williams, on the other hand, was not able to run as much this week as he was at this time a week ago.

"Mike's a little more of an issue because we have to make sure he can run full speed on Sunday," Carroll said.

Williams suffered a sprained left ankle in last week's game, an injury compounded by its proximity to the strained left foot he was still recovering from. Seattle prepared for this game as if Williams would not be available.

"We have to plan like he's not there, and fortunately, guys have practiced well," Carroll said.

With Williams questionable, Ruvell Martin is expected to be active for the game and rookie Golden Tate could factor more heavily into the passing game.

Notes

• Guard Chester Pitts is doubtful, expected to miss his third consecutive game after suffering an ankle injury. Mike Gibson remains the starting left guard, and Seattle will start the same offensive-line configuration for the third consecutive game, which would be the first time that has happened this season.

• Seattle promoted OT Breno Giacomini from the practice squad to the 53-man roster earlier this week, filling the spot vacated when DE Clifton Geathers was waived. Geathers did not appear in a game.

Danny O'Neil: 206-464-2364 or doneil@seattletimes.com