2015 Sleeper Series: Mariners Pitcher James Paxton

James Paxton is a starting pitcher for the Seattle Mariners. He will slot into their rotation as the 3rd starter in 2015, most likely. He is left-handed. His potential breakout season was cut short by injury in 2014 after only 74 innings. He showed promising signs befitting his top-100 prospect status. These are facts we can all agree on.

Now, it's 2015 and I'm looking at the Mariners depth chart trying to find guys that could be considered sleepers. Their rotation has two no-doubters in Felix Hernandez and Hisashi Iwakuma, Paxton, and then some shaky guys in Roenis Elias and J.A. Happ. Their infield is a mix of proven, boring veterans like Robinson Cano and Kyle Seager, and complete wild cards like the Chris Taylor/Brad Miller shortstop mess and Logan Morrison's latest injury at first. The outfield has some interesting guys, but I couldn't call them sleepers, as I don't think any of the trio (Dustin Ackley, Austin Jackson, Seth Smith) will do much better than last year and is worthy of the "sleeper" label.

So, I circled back and landed on Paxton. He qualifies as a sleeper despite his solid 2014 performance for two reasons: he only threw 74 innings due to a lat/shoulder injury combo, and he is currently the 60th starting pitcher taken in NFBC drafts (238 overall; see NFBC Results). First, let's address his on-field performance and then we can talk about his health concerns.

Below is a table that captures statistics that I find relevant about Paxton's 2014 season. It's a mix of the usual fantasy categories, some hand-picked sabremetrics, and a stat of my own.

This table shows that Paxton did have a great run in his short time. That ERA is excellent and was 36th best in baseball among 70+IP starters. Even his WHIP isn't too bad. His walk rate is above the league average and the strikeout rate is almost exactly average for starters. With that information, it sounds like he just got lucky, since his walk rate was high, his strikeout rate was average and somehow he produced good ERA and WHIP values. Well, that GB% column tells part of the story. The league average for starters was 44.6%, so he is well above that. In fact, he was 10th best in baseball for starters with at least 70 innings. His FIP and xFIP were both in the low to mid-3s also, so there isn't too much stranded runner or HR/FB luck going on.

Getting grounders is a useful way to make up for a lack of strikeouts and get easy outs and limit the damage from mistakes. I expect this trend to continue in 2015 and that is one reason I am bullish about Paxton.

As for the last two numbers in that table, his swinging strike rate is below the league average of 8.8%, so there is nothing to get excited about there. Or is there? The SPAM score of 7 is well above average (click here for a detailed breakdown of how SPAM was calculated and what it means). Only 26 pitchers in 2014 had a score above 7. He gets a good score because he throws hard (94+ MPH), gets above average ground ball rates on three pitches (fastball, cutter, and change), and gets above average swinging strike rates on three pitches (cutter, curve, and change). The swinging strike rates show there is actually room for upward movement on his overall strikeout rate. I am expecting an increase in strikeouts from Paxton this season. Also, Eno has updated his method (that I call SPAM) recently and Paxton still showed up high on the new list at #29.

He has velocity, he has the potential for increased strikeouts, and he excels at getting ground balls. So why is he the 60th pitcher taken in drafts? Well, there are two concerns that I touched on above: health and control. He had control problems in the minors and has always had an above-average walk rate. Last year, he actually had a walk rate on the low end of his track record. I don't think he will suddenly become a control artist like Maddux, but a modest improvement in control is very possible. With an uptick in K% to say, 22%, and a walk rate of 9.2% or so, he would now be above average in K%-BB%, which is a good way to spot a breakout pitcher.

Regarding his ouchies, bumps, and bruises: he had both a lat muscle strain and an inflamed shoulder in 2014 and missed a lot of time (April through July). He recovered fully from those injuries (or so we are told) and returned to start the last two months of the season. His velocity remained very stable after his return with the only noticeable drop occurring in his second-to-last start of the year against Toronto, when he only lasted 2 2/3 innings and gave up 8 earned runs. It bounced right back up to his average in his final start, so it really isn't anything to worry about. The biggest source of concern related to injury is the fact that his Zone% dropped from roughly 47% before the injury to 37% at the end of the year. His 5-game moving average shows a steady decline over those entire two months. Jeff Zimmermann will tell you that this can indicate playing through an injury. His release point and velocity don't show the same alarming trends, so I'm not too worried, but it should be noted.

Finally, I give you Steamer's projection and my own. You will see that Steamer is not very optimistic about him, while I am willing to take a chance on him improving and staying healthy. Disagree about Paxton? Let me know in the comments! Tschus!