SEATTLE— One hard fall by Ben Obomanu added to Seattle's depleted wide receiver corps.

It may also land an unlikely spot on the roster for someone.

Obomanu broke his clavicle early in Seattle's 23-16 preseason victory over the Oakland Raiders on Friday night. Obomanu was injured midway through the first quarter after making a 33-yard catch over the middle, landing hard on his shoulder. Coach Mike Holmgren revealed the injury after the game.

"That's a tough one, certainly," Holmgren said. "I feel bad for him. He was very much in our plans."

Asked if Obomanu may be placed on injured reserve, Holmgren said, "It's a possibility."

Obomanu was the most experienced of a young group of Seattle receivers being called upon to pick up for the absence of Deion Branch and Bobby Engram. Obomanu is in his third season with the Seahawks and had 12 catches last season. With Obomanu's injury, the only healthy Seattle receivers who caught passes last season are Nate Burleson and Courtney Taylor.

Obomanu was expected to backup Burleson, but was versatile enough to play all three receiver positions in Seattle's offense.

Holmgren remains hopeful Branch could begin practicing next week. Branch is still trying to recover from major surgery after a serious knee injury in last year's NFC playoff loss to Green Bay. Engram, the Seahawks' leading receiver from last year, broke a bone in his shoulder in the first preseason game in Minnesota and could be out into October.

"It's just an unusual situation with the numbers at wide receiver with all the injuries," Holmgren said.

If Obomanu is placed on injured reserve, the biggest beneficiary could end up being rookie Michael Bumpus or Logan Payne.

Undrafted out of Washington State, Bumpus has impressed during training camp and had a team-high 53 yards receiving on three catches Friday night.

"I feel like I did what I was expected to do. I feel like I didn't make any assignment errors," said Bumpus, who finished with eight catches in the preseason. "There are always things you can improve on but my job today was just to make it difficult on them and I feel like I did that."

Payne is experienced in Seattle's system and is a solid inside receiver. He had three catches on Friday, but also dropped one pass. Jordan Kent and Courtney Taylor are likely assured of roster spots as well, and with Charlie Frye's development at quarterback, the likelihood of Seneca Wallace seeing some time at receiver has significantly increased.

"It always comes down to the last preseason game and everyone shows up," Wallace said. "The coaching staff has some big decisions ahead of them."