Right-handed setup man Brandon League stands as the most-familiar name in that expected group and hard-throwing rookies Dan Cortes and Josh Lueke also have been mentioned prominently in the club's prospective plans.
But another guy to watch in that regard when pitchers and catchers report in Peoria, Ariz., on Sunday is Chris Ray, a former Orioles closer now two years removed from Tommy John surgery.
Ray, 29, turned down a Major League offer from another club and signed a Minor League deal with the Mariners, liking his chances enough to take that risk on a deal that will pay him $1 million in base salary if he makes the team, with playing time incentives that could add as much as another $1.025 million.
With Aardsma expected to miss at least the first few weeks of the regular season, Ray comes in as the most experienced closer in camp with 51 saves, 49 of those coming with the Orioles in 2006-07 before his elbow surgery.
After missing all of '08, Ray pitched 46 games for Baltimore in '09 and then 63 games while splitting time last year between Texas and San Francisco, the two teams that wound up playing each other in the World Series.
Ray wasn't on the playoff roster with the Giants, but he pitched fairly effectively for both clubs in putting up a 5-0 record and 3.72 ERA in 55 2/3 innings in the regular season. Now the Mariners feel he should be all the stronger, another year removed from his elbow reconstruction.
Mariners general manager Jack Zduriencik says the Tampa, Fla., native definitely figures in the mix for one of the late-inning jobs if he shows well in camp.
"Chris is going to be given every shot to make this club," Zduriencik said. "Here's a guy that has closed games out at times and he's a veteran. He's bounced back now healthy.
"In our talks with him, we laid it out, 'Chris, you have every opportunity to make this club. We'll give you every chance to be part of this bullpen Opening Day.' Certainly he has to come in and compete, but it's a nice opportunity for him."
Tony Blengino, the Mariners' special assistant to the general manager, believes the 6-foot-3 right-hander is close to being back to the pitcher who posted a 3.19 ERA and totaled 138 strikeouts in 149 1/3 innings his first three seasons with the Orioles.
"The arm strength is there," Blengino said. "His slider was an out pitch for him when he was at his peak and lots of times with arm issues, the last thing to come back is the secondary stuff. If that comes back, we have a chance to have the same guy who closed those games for Baltimore."
If Ray does close games for Seattle, he'll enhance his own value. A total of $500,000 of his potential incentives are tied into the number of games he finishes. The other half are based on number of appearances.
So if Ray pitches often and works his way into a prominent late-inning role, he'll do well for himself and the Mariners. And the club certainly is open to that sort of help, given the uncertainty over Aardsma's health and the inexperience of several of their other top late-inning candidates.