The Seahawks signed Tukuafu on Wednesday after electing to place starting fullback Derrick Coleman on injured reserve last Saturday. Turbin had served in the role on an emergency basis after Coleman broke his foot in pre-game warmups in St. Louis.
''I think it was an opportunity to get a physical addition to what we do on offense and I'm hoping that he'll fit in,'' head coach Pete Carroll said.
Tukuafu originally signed with the Seahawks as an undrafted free agent out of the University of Oregon in 2010. However, he was released before the season and signed with the San Francisco 49ers. Tukuafu spent the last four years in San Francisco before being placed on injured reserve with a concussion at the end of training camp.
The 49ers gave Tukuafu an injury settlement, which allowed him to sign on with a new team this season.
''It's real similar to the offense that we had with the 49ers,'' Tukuafu said. ''Smash mouth and stuff like that. I'm excited to come in and help out wherever I can and do my job.''
Tukuafu has appeared in 20 games over the last three seasons for San Francisco. He returned to Eugene, Oregon, to train in his two months as a free agent. The break gave him a chance to be home for the birth of his second child, Kingston, two weeks ago before the Seahawks began to show interest.
Seattle brought Tukuafu in for a workout last week before signing him Wednesday.
''When you're out for two months, you're kind of working off the cobwebs here and there but I'm ready to go,'' Tukuafu said.
Tukuafu played on both sides of the ball in San Francisco and Carroll said he could see time on defense for Seattle as well. He knows what it's like trying to tackle Lynch as a rusher, so he's excited to be paving a path for him instead.
''I love his style of play,'' Tukuafu said.
Turbin was willing to step into the role on a short-term basis, but he's happy to leave the job to Tukuafu going forward.
''It's refreshing,'' Turbin said. ''What's great about it, he's already come in and worked very hard trying to learn the offense. He's a physical being. It's good to have him on the team.''
Tukuafu has only had two days of work with the Seahawks offense but running backs coach Sherman Smith said he has no doubt Tukuafu will be ready to play against the Oakland Raiders on Sunday.
''He's a professional,'' Smith said. ''He takes his job serious. He wants to do a good job and he's going to take advantage of the opportunity.''
Notes: CB Richard Sherman (back), CB Tharold Simon (knee), DE Michael Bennett (toe) and C Stephen Schilling (knee) were new additions to the injury report and did not practice Thursday. ... With Sherman, Maxwell and Simon sitting out, Seattle only had two cornerbacks on their active roster available to practice in Marcus Burley and DeShawn Shead. Jeremy Lane did practice as well but is still on the injured reserve list and isn't eligible to return to the active roster until next week. ... The Seahawks signed TE Brett Brackett and WR Chris Matthews to their practice squad and released TE RaShaun Allen. Brackett was released from the 53-man roster on Monday. Matthews spent training camp with the team.
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