Should the Rays trade Jeff Niemann or Wade Davis?

After the Rays locked up Matt Moore to a extension that will keep him in a Rays uniform for at least the next five years, Andrew Friedman stated that Moore’s new contract does guarantee him a roster spot to begin the year. Why did Friedman say that if now the Rays have absolutely no reason to keep Moore in the minors anymore since he’s guaranteed money over at least the next five years? Well, it has to be that Friedman doesn’t want to tip his hand that he absolutely has to deal a starting pitcher this offseason because he simply has too many good ones. Who should that pitcher be?

In David Price, Jeremy Hellickson, and Moore, the Rays have three quality young pitchers they know they can rely on. James Shields is getting more and more expensive, but they know that he’s an integral part of their rotation and the Rays have have to blown away by an offer to trade him. That leaves three pitchers: Jeff Niemann, Wade Davis, and Alex Cobb. Niemann will be 29 in February, but he’s still relatively cheap, having earned under 1 million dollars in 2011. Davis is 26, but he’s a bit more expensive. He will earn 1.5 million dollars in 2012 before his salary jumps to 2.8 million dollars in 2013 and 4.8 million dollars in 2014 and several more costly options come into play. Cobb is just 24, and he’s still extremely cheap. Cobb may be stuck at Triple-A or in the bullpen, but he’s not going anywhere unless some team offers them a good deal for him. But for Niemann and Davis, they’re legitimately on the trade block and it seems clear that the Rays should trade one of them. But which one should it be?

Let’s start by comparing how Niemann and Davis performed in 2011. Niemann had a nice season overall in 2011, going 11-7 (the best winning percentage of any Rays starter) with 105 strikeouts (7.0 K/9), 37 walks (2.5 BB/9), and 18 home runs allowed (1.2 HR/9) in 23 starts, one of which was a complete game (that I attended and live-blogged here), and 135.1 IP. He posted a 4.13 FIP on the season, but actually a 3.73 xFIP as 12.6% of the flyballs he allowed went for home runs compared to the league average of 10%. He missed from early May to late June with a back injury, but after returning from that injury, he posted a 1.88 ERA, an 8.6 K/9, a 2.5 BB/9, and a 0.4 HR/9 in his first 7 starts back (43 IP). His FIP during that stretch was 1.88, but his xFIP during that time period was a much higher 4.07, actually significantly worse than his seasonal xFIP. Really that great stretch was just a fluke.

Davis, meanwhile, went 11-10 with a 4.45 ERA, 105 strikeouts (5.1 K/9), 63 walks (3.1 BB/9), and 23 homers allowed (1.1 K/9) in 29 starts and 184 IP. His FIP was actually worse than his ERA at 4.67, and his xFIP was even higher at a horrible 4.82. He allowed an incredible amount of flyballs, posting just a 36.2% GB%, and it cost him. Davis got off to a really nice start to the season, going 3-2 with a 2.77 ERA in 5 April starts with 15 strikeouts (4.1 K/9), 10 walks (3.0 BB/9), and 1 homer allowed (0.5 HR/9) in 33 IP. It’s pretty clear that his nice stretch was a completely fluke as he posted a 3.78 FIP and quite possibly the worst xFIP you’ve ever seen: 6.10. Davis’ real bright spots in 2011, were two nine-inning starts, one of which was a complete game (the other game went into extra innings). On August 24th against the Detroit Tigers, Davis was masterful, using 102 pitches to go all 9 innings, allowing 2 runs on 4 hits, striking out 6 while walking 3 in a game that the Rays won 3-2 in 10 innings. Even in that game, though, he allowed 11 groundballs, 13 flyballs, and 4 line drives. His FIP for the game was 4.31, and his xFIP was 4.74 (he allowed 1 home run in the game). On September 9th against the Red Sox, Davis came up big in an enormous game, using 114 pitches to 6-hit Boston, allowing just 2 runs and striking out 8 while walking none. His FIP for the game was a ridiculous 1.42. However, he allowed just 9 groundballs compared to 15 flyballs and 5 line drives, leading to a 3.59 FIP. Davis had his moments of greatness, but they all depended on the multiplicity of flyballs he allowed not leaving the park. There’s no denying that Davis experienced a sophomore slump in 2011.

But 2011 might not really be enough of a sample size. Let’s go back to Niemann and Davis’ major league career numbers. For his career, Niemann is 38-23 with a 4.16 ERA, a 6.7 K/9, a 2.9 BB/9, and a 1.1 HR/9 in 84 starts (4 complete games, 3 shutouts), 5 relief appearances, and 506.1 IP across 16 innings in 2008, full seasons in 2009 and 2010, and the partial season in 2011 due to his back injury. Niemann has never thrown 200 innings, with his career-high coming in his rookie season of 2009, when he tossed 180.2. His career FIP is 4.32 while his career xFIP is 4.18 and his career SIERA (another “true ERA kind of stat that weighs pitchers based on strikeouts, walks, and groundballs compared to flyballs) is 4.20. Looking at his FIP, xFIP, and SIERA compared to his ERA, it appears that Niemann has been somewhat unlucky because the outstanding Rays defense usually leads to Rays pitchers consistently outperforming their FIPs. Nevertheless, Niemann has been a solid big league hurler the past few seasons, posting a 97 ERA+ (ERA compared to the league average of 100 adjusted to ballpark, higher is better), a 107 FIP- (FIP compared to the league average of 100 adjusted to ballpark, lower is better), and a 99 xFIP- (ditto FIP- except for xFIP). For what it’s worth, according to Baseball-Reference.com’s Neutralized Pitching (explained here), Niemann does much worse when taking out the effects of Tropicana Field, posting a 4.81 career ERA, 6.7 K/9, 3.3 BB/9, 1.3 HR/9, and a 4.77 FIP. Still, Niemann is a dependable veteran pitcher that another team would be happy to have.

Davis, meanwhile, is 25-22 with a 4.22 ERA in his career with a 5.9 K/9, 3.2 BB/9, and a 1.1 HR/9 in 64 starts (2 complete games and 1 shutout), and 388.1 IP. After tossing 36.1 IP in 2009, Davis threw 168 innings in 2010 and 184 in 2011. Davis’ career FIP is 4.55, his career xFIP is 4.61, and his career SIERA is 4.61. Unlike for Niemann, the Rays defense has certainly done Wade Davis some favors as he has outperformed his FIP, xFIP, and SIERA for his career by a pretty significant margin. For his career, Davis has a 92 ERA+, a 107 FIP-, and a 116 xFIP-, so while he has been decent, he hasn’t been anything special. As expected, Davis gets drilled by B-Ref’s Neutralized Pitching, with his career ERA jumping to 5.12 and his K/9 coming in at 5.9, his BB/9 at 3.7, his HR/9 at 1.3, and his FIP at 5.13. Davis has been more durable than Niemann, but he has not been nearly as good.

But now matter how much anybody tells you, the stats don’t tell the whole story. What makes a pitcher good or bad or somewhere in between is his pitches. What matters is how hard he throws each one of his pitches and with how much movement in addition to with how much command and control. Also, pitchers have to find the right balance in throwing their pitches. Let’s look at the 2011 Pitch F/X data for both Niemann and Davis, from TexasLeaguers.com. Except instead of giving you the table form that you can’t understand, I’ll give you what I like to call a movement chart.

There’s a more detailed explanation here, but in a nutshell, the chart shows the average movement on a pitcher’s pitches if they started in the absolute center of the strike zone. The endpoints of the lines indicate the net movement of the pitches while the way the lines look is an approximation of how the pitches travel in the air. The key states what percentage of the time each pitch was thrown and what each pitch’s average velocity was.

So how do we compare these two charts? Well, the eye test shows that Niemann’s and Davis’ pitches moved just about the same. The primary difference was that Niemann primarily threw his two-seamer (light blue) while Davis primarily threw his four-seamer (dark blue). In order to see whose pitches’ really moved better, we’ll use Weighted Absolute Net Movement, which means taking the resultants of each of pitch for these two pitchers (the square root of the vertical movement squared plus the horizontal movement squared), and weighting the results through how often each pitch was thrown to come up with a mean movement value. Niemann’s WANM comes out to 9.08 inches while Davis’ comes out to 9.40 inches, just a bit higher. But the key factor is that Niemann’s pitches featured much more downward movement than Davis’ leading to a 46.0% GB% compared to Davis’ horrible 36.3% mark. Niemann’s pitches on average moved 3.70 inches upward vertically. Davis’ pitches moved 6.47 inches upwards on average, primarily due to his high-rising fastball that he used over half the time. It’s OK to pitch up in the zone, but when you don’t get your pitches up enough, hitters destroy them. That’s what happened to Davis in 2011, leading to a staggering 72 extra-base hits against him. Niemann kept the ball primarily down, and while he did still allow some home runs, he allowed a fewer percentage of extra-base hits, with 8.7% of all plate appearances against him ending with an extra-base hit compared to Davis’ 9.1% mark. Why such the small difference? Because Niemann couldn’t throw hard enough nor with enough movement to fool hitters often enough to be a dominant pitcher. Despite that, based on this 2011 movement chart, Niemann seems like the better threat long-term. He keeps the ball down better and has a variety of weapons he can use to get hitters out, unlike Davis, who had to build completely off his fastball, which was pretty straight, featuring practically only vertical movement.

But just like we went back to career stats for Niemann and Davis, we really should go back to career Pitch F/X for these two pitchers because the movement on a pitcher’s pitches vary from game to game and over the course of a season, sometimes you have great movement more often and sometimes you have horrible movement more often. The career Pitch F/X will make the data as legitimate as possible. Let’s take a look.

F0r both pitchers I omitted pitches that Pitch F/X termed as “fastballs”, neither four-seamers nor two-seamers, and cutters from both pitchers that they used less than 1% of the time. This prevents the percentages in the key from reaching 100%, but there’s no point of wasting your time with pitches that were vaguely identified and could have moved in a multitude of ways, or pitches that Davis barely even threw. both of which make an average movement line useless.

From the eye-test, we see once again that Niemann’s and Davis’ pitches move very similarly. But we see something very interesting when we compare Davis’ career average fastball movement with his 2011 fastball movement. Here’s those two pitches on one chart.

It’s clear that Davis’ career fastball movement is better than his 2011 movement, featuring just under an inch more horizontal movement in slightly more vertical movement. But like I said before, the movement on a pitcher’s pitches can vary from season to season. However, here’s the problem: if you look back at the key’s from the previous two charts, you see that in 2011, Davis’ average fastball velocity was a bit lower than his career average velocity. So in 2011, not only did Davis have less movement on his fastball, but he also threw it with less velocity. At the beginning of the season, Davis remarked that he was going to take some velocity off his fastball in order to get more movement on it. That completely failed. But if Davis can maintain the better velocity and the better movement on his fastball, it can be an effective pitch. According to Fangraphs, Davis’ fastball registered at 2.9 runs above average in 2011. But considering how much he used the pitch, that was disappointing. In 2010, Davis’ fastball was 7.0 runs above average, and that made him a better pitcher. Davis not establishing his fastball as a good pitch made all his other pitches less effective and he basically had to stick with his fastball because hitters were sitting on his other pitches. (That also happened in 2010, but to a lesser extent.) If Davis can establish his fastball enough that he can mix in all his other pitches, he can be the pitcher that the Rays saw enough flashes of in 2010 to give an extension.

Comparing Niemann’s and Davis’ career movement charts, Niemann has a 8.61 WANM while Davis comes in at 9.21 WANM. When you factor in the pitches I omitted (the “fastballs” and scarcely used cutters), Niemann’s WANM goes up to 8.88 while Davis’ WANM goes up to 9.38. Considering that Davis also throws harder than Niemann, it’s clear that Davis will  be the better pitcher long term.

So who should the Rays trade? I think it has to be Niemann. Davis was not a good pitcher in 2011, but he has the potential to be much better than that. He’s not quite as cheap as Niemann, but he’s still cheap. Davis has the upside to be a good 3rd starter in the major leagues, and the Rays shouldn’t give up on him yet. Niemann is what he is at this point. He’s a solid big league starter, and it’s convenient for teams that he is still cheap. Unless another team blows the Rays away with an offer for Davis, Niemann is the pitcher that the Rays should trade.