Let's not convert Tom WIlhelmsen into a starter

As it stands right now, the Mariners have four of the five spots in the pitching rotation locked up. It goes like this: Felix Hernandez, Hisashi Iwakuma, James Paxton, Taijuan Walker and a player to be named later. Unfortunately, the Mariners probably won't switch to a four man rotation to give us King Felix even more often, so the question of who will be the fifth starter remains.

Most likely, that fifth starter will be someone the Mariners pick up in a trade. Or perhaps they re-sign a resurgent Chris Young. Either way, the Mariners rotation is in a very good position to start spring training rather stable. It is one less thing on a laundry list of things to pay attention to early in the season.

There was a bit of chatter in the midseason about converting Tom Wilhelmsen into a starter and tossing him in at the end of the rotation. After losing the closing gig in, Wilhelmsen seemed to find his place and passion in baseball again last year. He became the one of the first guys to go to to eat up innings, pitching two innings or more in relief 16 times last season. He even logged a couple of starts. Just because he did all of that well doesn't make him a candidate for starting next season.

I was going to look for a bit of data amongst old relievers turned starters to try and find if there was any storyline within. Realistically, the sample size is too small and too varied to make any sort of definitive statement about the matter. For every Chris Sale, there is Daniel Bard. For every C.J. Wilson, there is Neftali Feliz. Jonah Keri took a look at the issue at hand in an article on Grantland back in 2012, and came away with the same mixed bag of data.

In Keri's article, it starts to get more to the point that converting a reliever into a starter isn't something you can take a hard look at numbers on and come away with a blueprint of who it works on and who it doesn't. Rangers pitching coach Mike Maddux spoke with Keri on the matter, and as the coach for a team that tries the conversion more often than most, holds a bit of weight on the matter.

"You have to develop your mind and body so you sustain the intensity you had as a reliever, so you can do it for nine innings," Maddux said. "Instead of it being a save situation, it's a winning situation - you have to shut ‘em down in the first ... and again in the second, third, and so on. If you try to pace yourself, I don't know if that's going to work out. Just go as hard as you can until you run out of bullets."

Wilhelmsen seemed to have that mind set. He spoke with Bob Dutton of the News Tribune prior to his start on Sept. 25 against the Toronto Blue Jays. Wilhelmsen said he would take his bullpen approach to the mound for the start.

"I don't know anything different. Try to get strike one. I mean, it's clearly different, but I'm not expected to go seven innings. I'm going to do what I did the last start. I felt fine after it."

For what it is worth, he finished the day with a line that more resembled a bullpen appearance, going 1.1 innings, giving up two hits and walking two more batters before getting pulled. Of course, one short, spot appearance doesn't mean much in the grand scheme of things.

2012 is a solid primer for how random the results are for converting relievers to starters. At the end of 2011, Sale, Feliz, Bard and Aroldis Chapman were all set to make the jump to the big guy on the mound. Sale successfully did, Feliz got injured, Bard fell apart and Chapman never did. Four different pitchers ended up with four different results. In Chapman's case, he was one of the top closers, and his value resided more in his ability to dominate the end of the game then carry the Reds at the beginning.

Back in the day, Nate Silver determined that the typical starting pitcher will have an ERA approximately 25 percent higher than the typical reliever. For Wilhelmsen, going off his career numbers, theoretically as a starting pitcher he would have an ERA of 3.64. Last year, that number would have placed him just a shade above Chris Young.

The Mariners aren't desperate for pitching. Theoretically, Wilhelmsen could turn into a solid starter. Even more theoretically, he could do nothing with the role. The Mariners aren't looking for a diamond in the rough to become the No. 2 guy behind Felix. The Mariners are looking for a No. 5 starter, and as the success of Young can attest to, it isn't  hard to find serviceable No. 5 starters in the league without having to take much risk.

Wilhelmsen found value with the team against last year as an important piece of an important bullpen. For the time being, he'll most likely stay where he is most valuable.