Seattle Mariners: What to Expect from the Starting Rotation in 2015

It's no secret: The Seattle Mariners regained relevance last season due in large part to their starting rotation.

As general manager Jack Zduriencik puts the finishing touches on 2015's roster, however, that may not hold so true as the M's make their first playoff push since the early 2000s.

Last year's rotation was a veteran-laden group of pitchers, complemented by rookie surprise Roenis Elias and a revolving door that was the No. 5 spot. There's more unknown about the 2015 group, but there's far more potential, too.

That comes when you're expected to run out three pitchers with a year or less of major league experience on their resumes. Let's take a look at the group of six pitchers battling for the five rotation spots.

All stats via FanGraphs and projections by Steamer.

*Steamer projects 48.0 IP for Walker, resulting in lower projected WAR.

One thing the Mariners have going for them is the top of their rotation. They possess a perennial Cy Young candidate and one of the most effective No. 2s in baseball and certainly the American League West. However, just one pitcher in the projected rotation threw 200 innings last season.

The Atlanta Braves teams of the mid-1990s set the standard for the modern major league rotation: Combine for at least 1,000 innings from the starters. Excluding Walker, this group combined for just 830.2 last season—that's a big jump to make for young pitchers.

Felix Hernandez is a relatively known commodity. Barring injury, the King will throw more than 200 innings of exceptional baseball. The rest, however, are more mysterious. Yes, even Hisashi Iwakuma.

In his five September starts last season, Iwakuma allowed 21 runs (all earned) in 23.2 innings. He averaged fewer than five innings per start.

At 33 years old, Iwakuma is exiting his prime years and entering the back end of his career. In 2013, his second MLB season, he threw a career-high 219.2 innings—don't expect those kinds of numbers again. Iwakuma could hit 200, but he only did so twice—201.2 and 201.0—in his 10-year Nippon Professional Baseball career.

That's not to cool anyone's jets on the Mariners' chances in 2015. By all means, they are the favorites in the AL West. And they have the luxury of starting pitching depth, which could alleviate the need for their young starters to drastically increase their innings.

It's essentially the same group as last season, except with J.A. Happ replacing Chris Young. Regardless of your thoughts on the Michael Saunders-Happ trade (here are Lookout Landing's Matt Ellis'), it provided the M's a more projectable middle-of-the-rotation starter. 

Young was a huge surprise last season, but that sparkling 3.65 ERA can't be expected to be maintained for another season, especially not with a 5.02 FIP. Young remains unsigned on the free-agent market.

It doesn't sound like Happ will need to compete for his rotation spot.

"We didn’t acquire J.A. Happ to pitch in the bullpen," manager Lloyd McClendon told reporters at the winter meetings. "We gave up an everyday player for a starting pitcher. We expect him to be in the rotation."

A spring training battle is unavoidable, though. Barring injury, there are six starters for five spots. There's another name in the mix, too: Erasmo Ramirez.

The 24-year-old right-hander has had stints with the big league club every season since 2010. Each one has been progressively worse, though—not what you want to see from a young pitcher. Those results have resulted in Ramirez having exercised all of his options. 

This forces the Mariners' hand a bit. Based on previous results, he shouldn't be in the competition for the rotation. But he's also still a young pitcher, who has had limited major league success—usually a commodity organizations don't want to give up.

But in order to keep him and not on the big club, he'll have to pass through waivers.

Ramirez would likely be claimed, so if the Mariners don't want to lose him, they could either keep him as a long reliever and spot starter or their No. 5 starter.

Although the decision seems trivial on the surface—keep or cut a mediocre MLB pitcher—it will result in a domino effect.

If Ramirez makes the roster, that's one of 25 spots, and at most, one of 13 pitchers' spots. It means whoever of that aforementioned group of six doesn't make the rotation will almost certainly start the season at Triple-A Tacoma.

The rotation is similar to the team, as a whole. It's safe to be excited—you should—but do so with cautious optimism. Personnel-wise, this is an upgraded group. However, it may not outperform last year's because, well, last year's significantly outperformed its talent level.

With so many variables in the rotation and significant upgrades offensively, the Mariners, for the first time in about a decade, could find themselves relying on their bats rather than their arms.

Evan Webeck is a junior at Arizona State University, studying journalism at the Walter Cronkite School. He's interned at Sports Illustrated and covered ASU football. Follow him on Twitter or email him at ewebeck@asu.edu.

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