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Over the past five seasons, the Seattle Mariners have seen flashes of Michael Saunders’ upside, but the talented outfielder has been unable to sustain success for the course of an entire season. In 2014, Saunders finally appears poised to put it all together for an extended period of time.

Saunders made regular appearances on top-prospect lists coming up with the Mariners, but has only managed a career line of .228/.297/.376. Approaching 1,700 plate appearances entering the season, 2014 looked to be a critical year for Saunders’ future, as he would either fully realize his potential or be relegated to a fourth outfielder role moving forward.

Despite that less-than-stellar slash line, Saunders has brought some value to the Mariners over his career. Saunders has sprinkled in enough power and speed to post a wRC+ of 108 in 2012 and 98 last year, meaning he’s been basically a league-average hitter.

With plus defense in the corner outfield spots, Saunders posted a respectable 3.2 WAR over those two years.

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Those numbers were bolstered by four-to-seven week stretches where Saunders would excel in every aspect of his game. But for whatever reason, Saunders would then go into prolonged horrific slumps, knocking his final numbers down to pedestrian levels.

One of the biggest “what ifs” of Saunders career came early in the 2013 season. Saunders was tearing the cover off the ball in the World Baseball Classic and through Seattle’s first 10 games before injuring his shoulder making a catch against the wall on April 10. He would miss three weeks and was unable to get in a good rhythm again until July.

But this year, Saunders has an improved plate approach that indicates he might be able to keep up his current rate of production. Per FanGraphs, Saunders has been worth .7 WAR in 44 games and could move closer to being a three-win player if he stays healthy.

Saunders had a limited role in April and struggled mightily, but has hit well enough in May to raise his line to .273/.326/.405. He missed a few games with a knee problem, but fortunately was able to maintain momentum and has been one of the most important Mariners hitters over the past few weeks.

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With the demotion of Abraham Almonte in early May, Saunders got a chance for regular playing time in either the leadoff or No. 2 spot for the Mariners. Saunders talked to Adam Lewis of MLB.com about his approach as a leadoff man before an April 26 game against the Texas Rangers:

I'm just going to try to put up a professional at-bat. Depending on the situation, you usually only lead off the game once and that's your first at-bat. We've seen [Colby] Lewis before. I'm not necessarily going to go up there and take pitches. I'm going to be selectively aggressive, and that was my mindset when I was leading off last year. My main goal is to get on base.

Saunders didn't show much of that in the past, but has backed it up in 2014 with some encouraging plate discipline numbers that suggest Saunders’ approach is indeed improving.

According to FanGraphs, Saunders has swung at a career-low 22.2 percent of pitches outside the strike zone this season. That in turn has helped lead to a contact rate of 84.1 percent, a huge jump over any other point of his career.

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Saunders is striking out less, too. His strikeout rate currently stands at 18.2 percent, down exactly seven points from a year ago.

In the past, we've seen Saunders shorten up his swing too much and struggle with pitches low and away. A look at his whiff chart on brooksbaseball.net shows that Saunders swings and misses most at those pitches, but has improved in 2014 and is also doing a better job of making contact on pitches high in the strike zone.

If Saunders continues these trends, he will finally avoid the dreaded prolonged slump he’s been prone to.

The two things the Mariners would like to see more of from Saunders this year are speed and power. Saunders hit 19 home runs and stole 21 bases in his career-best 2012 season. If he can approach those numbers in 2014, he will be a very valuable player for the Mariners moving forward.

He’s still got some pop, as sometimes the ball just explodes off Saunders’ bat. Saunders has two home runs this season, including this impressive shot May 17 against the Minnesota Twins:

Saunders also hit one off of the Hit it Here Cafe in Safeco Field last summer, which takes some special power.

There’s no doubt that Saunders is going to be critical to the Mariners in 2014 for a number of reasons. The Mariners have rotated through a number of players in the all-important No. 2 spot this season, finding little success.

As Seattle appears to have found something with James Jones in the leadoff spot, Saunders is the logical choice to bat second. Announcer Aaron Goldsmith points out that Saunders has been successful in the role so far:

If the Mariners are going to score runs, Saunders needs to get on ahead of Robinson Cano. Manager Lloyd McClendon talked to Greg Johns of MLB.com about the advantage Saunders has batting between Jones and Cano.

"I think it has a lot to do with the guy hitting in front of him. And the guy behind him, too, but the guy in front of him can run a little. Anytime you take a little concentration away from the pitcher, it's going to help."

The question now becomes if McClendon has faith in Saunders to bat him second on a regular basis. Saunders has been in and out of the lineup, but Jason A. Churchill believes he should play every day barring injury:

Churchill is absolutely right. On the surface, it makes sense that the Mariners would try to get more right-handed bats in the lineup, as they are lefty heavy. But Saunders has actually hit better against left-handers in 2014 and should not be a candidate for a platoon.

But it’s also important for the Mariners to finally see their patience with Saunders rewarded. David Schoenfield of ESPN’s SweetSpot blog highlights the number of top prospects the Mariners have been patient with over the past four years:

The Mariners have been waiting for four of those homegrown players to break out forever and brought in Logan Morrison with the hope that he would finally meet his potential. If just one or two of them can step up, the Mariners will be a much more dangerous club in 2014 than previously expected.

Saunders is the guy to finally reward that patience. With his existing skills and improved plate approach, he will be a critically valuable piece for the Mariners over the rest of the season.

All stats per FanGraphs unless otherwise noted.