The 6-foot-6 right-hander will be used now as a middle-innings reliever as Danny Farquhar has secured the closing job, converting 11 of 12 save opportunities since taking over that role.
"I'm going to use him in multiple roles, really," manager Eric Wedge said. "I'll just ease him in and see what happens. The sooner we get Tom in there and find out where he is, the sooner we'll get a better idea of how we can use him."
Wilhelmsen said he was ready for anything.
"I might even play shortstop or something," he said with a laugh. "I was starting there, relieving. I was all over the place. Maybe DH. Who knows? We'll see."
Though Wilhelmsen started two games in Tacoma, that was just to control his outing and he never threw more than two innings. The club considered converting him to a starting role a year ago, but that is not in the plans now, Wedge said.
"I still feel with his personality, he's still more of a bullpen guy," Wedge said. "I think he has the pitches to be a starter if he needs to be, but now you're talking about stretching a guy out, taking years to stretch a guy out where he can be a viable starter throwing 170-180 or 200 innings. That's not something that happens overnight without putting him in harm's way."
Wedge acknowledged Wilhelmsen didn't put up great numbers in Tacoma, but said he worked on locating his fastball and getting ahead in counts quicker.
"We've seen him come up here before and do well, even better than he did in the Minor Leagues. So hopefully he can flip that switch again," Wedge said. "I feel strongly that he's going to be a part of this. In what role? I don't know. He has too big an arm and too much experience and too much success in a vital role up here not to be. So I'm hoping all these trials he's gone through will ultimately help him be a better bullpen guy because of what he has gone through. He's seen both sides of it."
What exactly was Wilhelmsen focusing on in Tacoma?
"Throwing strikes. Just trying to throw strikes," said the big right-hander. "It's kind of been that way, not just the last month. That's what you're always trying to do. I guess if my numbers weren't good and I'm working on throwing strikes, that means I'm throwing strikes because they're hitting 'em. So I was successful in doing what I was supposed to be doing."
Wilhelmsen is 0-3 with a 4.37 ERA in 47 games this season for Seattle after going 4-3 with a 2.50 ERA in 73 appearances in 2012.