In a couple of weeks, Kevin Slowey will celebrate his 30th birthday, and the veteran right-hander is lined up to make his 105th career big league start on Sunday.
Slowey's counterpart in the series finale on Easter is a right-hander set to make his 2014 debut.
Seattle will send right-hander Brandon Maurer to the mound in a game that wraps up Miami's six-game homestand.
Both teams are going with makeshift starters. The Marlins, who have taken the first two in the series, go for the sweep, while Seattle seeks to salvage one.
Slowey is filling the spot that opened when Jacob Turner (right shoulder sprain) was placed on the disabled list on April 9, retroactive to April 4. Slowey, who opened the season as a long reliever, is getting the nod after Brad Hand struggled in two previous starts filling in for Turner. Hand now moves back to the bullpen as a long reliever.
In Slowey, the Marlins have a veteran capable of adapting to a variety of roles. Asked to describe his role, Slowey said: "Undefined."
At this stage of his career, Slowey isn't picky about how he is used. Early in his career, he was a starter with the Twins. But he's also dealt with injuries, which have given him perspective.
"I think part of it is you come back from being hurt," Slowey said. "The more that you play, the more you realize there are a lot of roles to be filled in the clubhouse. The way to stick around and the way to be in the Major Leagues is to fill a role, no matter what that role may be.
"More often than not, it's not up to you to determine your role. Someone else is going to tell you, 'This is where we feel you fit in, go and do it.'"
Slowey has faced the Mariners five times in his career, and he's 2-2 with a 4.18 ERA.
Maurer arrived from Triple-A Tacoma on Friday after being told on Wednesday he would probably be the starter, but it wasn't certain with other candidates in the mix. He will officially be added to the roster on Sunday, which means Seattle will make a corresponding move.
The Mariners have had a series of injuries to starting pitchers, leading to Maurer getting the nod. James Paxton is on the disabled list with a strained oblique. His replacement, Blake Beavan, landed on the DL on Tuesday with a sore shoulder. Top prospect Taijuan Walker was shut down earlier this week with shoulder tightness.
"Just try to go out there and throw my best, not look too much into it opportunity-wise," Maurer said. "Just go out there and try to win a ballgame."
The young right-hander is looking to stay even-keeled in his season debut.
"Control my breathing," Maurer said. "Staying calm is the biggest thing. As long as I do that, I'll be OK."
Maurer went 5-8 with a 6.30 ERA in 22 games (14 starts) in 2013. He is building his arm strength after battling a back injury during Spring Training. The righty had a 2.16 ERA in four outings (one start) for Tacoma.
"It's a different ballgame this time, because I was obviously quite a wreck last year," Maurer said. "Much more comfortable this year."
Marlins: Figuring out the cleanup spot
Garrett Jones, who has been batting cleanup against right-handed starters, was not in the starting lineup on Saturday as Seattle went with a lefty.
If teams look to intentionally walk Giancarlo Stanton, or pitch around the slugger more, manager Mike Redmond is weighing his cleanup options. It could be Jones, Casey McGehee or Jarrod Saltalamacchia.
"If that starts happening, we're going to rely heavily on the guys batting behind Stanton, too, to get those big hits or drive in those runs," Redmond said. "I like the guys that we have. I think they've done a nice job behind him. We'll see how that plays out.
"We'll see what makes this lineup work the best, and we'll go from there."
Mariners: Franklin to the outfield?
Considered Seattle's second baseman of the future until Robinson Cano's signing, Nick Franklin could soon make his outfield debut.
Since being recalled on Wednesday, Franklin has started a game at second and another as designated hitter. He has gone 1-for-8 with a triple, a walk and two runs.
Franklin played in 96 games (90 starts) at second last season, in addition to making three appearances (two starts) at shortstop. Of late, he has been practicing in the outfield.
"He showed in Spring Training that he could go out there and play, and the work he did in practice and Spring Training was pretty good too," Mariners manager Lloyd McClendon said. "If I had to put him out there, I would feel comfortable. I wouldn't have a problem at all."
• Jacob Turner is scheduled to throw a bullpen session on Sunday, and after that, the Marlins' right-hander is slated to begin his rehab assignment next week at Class A Jupiter. Turner, on the disabled list with a right shoulder sprain, is scheduled to pitch for the Hammerheads on Wednesday.
• With his third-inning double on Saturday night, Christian Yelich extended his career-high hitting streak to 13 games.
• Stanton was intentionally walked once, making it four times in the series.
• The Marlins have homered in 10 straight games, their longest stretch since 13 straight in 2009.
• Maurer will be the seventh starting pitcher for the Mariners through 18 games this season. They used 11 last year and just seven in all of 2012.
• Seattle pitchers are looking for their first hit in Interleague Play since 2012.
• Dustin Ackley, who broke up Henderson Alvarez's no-hit bid in the sixth inning on Saturday, has at least one hit in six of his last seven starts.