Seattle Mariners: Analyzing Edwin Diaz's Brilliant Rookie Season

Seattle Mariners closer, Edwin Diaz, has been one of the more dominant relievers in baseball in just his first season in the majors. But what’s behind the rookie’s early success?

It’s not every day that a reliever makes his major league debut and becomes a dominant closer in the same season, but that’s just what Seattle Mariners closer Edwin Diaz has done in 2016. After making his major league debut on June 6, the 22 year-old did not collect his first save until about two months later. Since then, Diaz has been on a roll, blowing only one save in 17 chances.

However, looking past his save percentage, all of his peripheral numbers point to Diaz being one of the better closers in the MLB. Not only does the young right hander have an ERA of 2.25, he has the highest strikeout rate of any pitcher in the league, setting down out just under 16 batters per nine innings. Also, his strikeout-to-walk ratio sits at an impressive 5.13 and he’s been good at not falling victim to the long ball, allowing just one home run since taking over as the Mariners’ closer.

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We typically think of a dominant late inning arm as a guy with a bulldog mentality that can light up the radar gun and get putouts. Diaz does not shy away from being that pitcher. According to FanGraphs, he averages just about 98 mph on his heater, throwing it 70 percent of the time when he takes the mound. He mixes his electric fastball with a slider that helps the young hurler keep batters off balance. The slider isn’t as crisp as you would like it to be, as he does have a tendency to leave it in the center of zone at times. Nevertheless, he has the arsenal you would expect when you look at how frequently he gets swing and misses.

Just watching Diaz, you can see why he’s been so successful in his first season in the bigs. He does not lack confidence and isn’t afraid to challenge hitters with his fastball. Most of the time, his opposition doesn’t stand a chance anyway. Like many late inning relievers, he has some extra motion in his delivery, but that should be seen as more of a distraction than a concern because he’s only facing a few batters every outing. His control could use some work as he walks just over three batters per nine innings, but it is not a huge problem being that it’s not unusual for high quality closers to let up some free passes. It’s always encouraging when what you watch matches up with the numbers you see, and that seems to be the case here.

In terms of where he ranks among the elite closers in the game, there is no question that the Mariners have one of the best in all of baseball. Granted, he does not have the pedigree of Craig Kimbrel, Aroldis Chapman, Andrew Miller, Zach Britton or Kenley Jansen. But I would argue that he does have the stuff to at least be mentioned in the same conversation as any of those guys.

Historically, closers are much more durable than their starting pitcher counterparts and can still hold up as they progress later into their careers. However, Major League Baseball does have quite a few a up and comers that are sure to make their way up the relief pitching ladder. Along with Diaz, Roberto Osuna has been phenomenal the past two years, Jeurys Familia leads the league in saves, Alex Colome has broken out in Tampa Bay and 25 year-old Ken Giles has rebounded after a rough start with the Astros.

The Mariners have to feel like the have another great one on their hands as he’s been invaluable to the team’s recent resurgence in the AL wild card race. It’ll be very interesting to see how Diaz reacts to all the success he’s had in 2016. But from what we’ve seen far, I expect that the 22 year-old will continue to be an elite late inning option for many years to come.

Next: Francona has Indians poised to win AL Central

Where do you think the Mariners closer ranks among today’s closers? Share your thoughts in the comments below.

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