Jake Arrieta: NL Contact Manager Of The Year

It would be an understatement to say that these are pretty heady days to be a Cubs’ fan. In the last two games of the NLDS alone, an age-24-or-under phenom who will be under team control for the next five years or so seemingly drilled a ball into the stands or onto a scoreboard every five minutes or so. The present is extremely bright, and the near-term future potential seems nearly limitless. At this point, it might be prudent to take a step back and pay a little respect to the player who made it all possible, whose incredible second half cemented the Cubs’ wild card spot and then propelled them past the Pirates in the wild card game, ace starter Jake Arrieta.

These Cubs have been built quickly, and have excelled in many talent procurement areas. Hitting on high-end position player draft picks? Check, thanks to the likes of Javier Baez, Kris Bryant and Kyle Schwarber. Attacking the international market? Check, thanks to NLDS wunderkind Jorge Soler. Don’t forget the trade market, either. Anthony Rizzo was stolen from the Padres, but the biggest theft of all was the acquisition of Arrieta, along with key bullpen cog Pedro Strop, from the Orioles for Scott Feldman and Steve Clevenger.

Like our AL Contact Manager of the Year, Marco Estrada, who turned 32 in July, Arrieta wins NL honors in the very first season in which he qualified for an ERA title, at a fairly advanced age (29). Unlike the Blue Jay righty, Arrieta excelled in every way a pitcher can be measured, by missing bats, minimizing free passes — you name it — and is a leading contender for NL Cy Young Award honors.

Neither Estrada (originally a sixth-round draft pick) nor Arrieta (a fifth rounder in 2007 out of TCU), were sure thing, top of the draft guys. While Estrada was a college performer who was short on raw tools, Arrieta was a little different. He was highly regarded enough to be drafted out of high school and junior college prior to signing with the Orioles, and likely would have been drafted much higher than the fifth round had the event been held in the fall of 2006. Arrieta oozed tools, but at times struggled to put it all together.

This trend continued through his minor league career. He was good, but not great, at his various minor league stops, posting a 36-28 record and 3.18 ERA while recording a 481/206 strikeout-to-walk ratio (K/BB) in 492 innings, and generally wasn’t among the younger pitchers at each level. Each year, I compile my own ordered minor league lists of top full-season-league position player and starting pitcher prospects based on performance and age relative to league and level. These basically serve as follow lists, with the orders then tweaked based on traditional scouting methods. While Arrieta’s tools were such that he made Baseball America’s Top 100 Prospect list, encompassing position players and pitchers, on two occasions, peaking at #67 prior to the 2009 season, he didn’t fare as well on my starting pitcher-specific list, qualifying twice and peaking at #54 after the 2009 season.

This marked him as a pitcher with promise, but not a bankable future star. His early major league performance was uneven, to put it mildly. Now, ERA has been proven to be a statistic with limited value, but this series of numbers — 4.66, 5.05, 6.20 and 7.23 — in that column of his record in his four seasons as an Oriole didn’t exactly breed confidence, and the upward trend wasn’t so promising, either. Kudos to the Cubs for flicking the switch seemingly immediately after the July 2013 trade; he has a 37-13, 2.26 record as a Cub.

How did he get it done this year? Let’s take a detailed look at his 2015 performance by examining his plate appearance frequency and production by ball-in-play (BIP) type data. First, the frequency information:

Before you even get to the batted balls, Arrieta sets a strong foundation with his exceptional K and BB rates. His 91 K rate percentile rank obviously sits near the top of the NL, and isn’t exactly a new thing for him. In fact, over fewer innings in 2014, his K rate percentile rank was actually higher, at 96. Well above league average control is something new for Arrieta, however. Prior to posting a 27 BB rate percentile rank in 2015, he posted BB rate percentile ranks of 90 and 95 in 2010 and 2011 for the Orioles, before improving into the league average range at 49 and 44 in 2012 and 2014. Commanding the baseball was job #1 for Arrieta on his road toward becoming an ace.

The eye-catching item among his BIP frequencies is clearly his grounder percentile rank of 94. This too was a major 2015 breakthrough. Prior to this season, he had been about a league average grounder generator, with his grounder percentile rank peaking at 70 in 2011 and bottoming at 30 the following season. His near league average liner rate (49 percentile rank) actually was also a positive development for Arrieta; in three of his four previous MLB seasons, he had posted a liner rate percentile rank of 66 or higher, maxing out at 96 in 2012.

A very strong frequency profile; lots of Ks, relatively few BBs, and tons of grounders. That builds in plenty of margin for error on batted ball authority. Let’s check out Arrieta’s production allowed by BIP type to see how he fared in that area in 2015:

The actual production allowed on each BIP type is indicated in the batting average (AVG) and slugging (SLG) columns, and is converted to run values and compared to MLB average in the REL PRD (or Unadjusted Contact Score) column. That figure is then adjusted for context, such as home park, team defense, luck, etc., in the ADJ PRD (or Adjusted Contact Score) column. For the purposes of this exercise, sacrifice hits (SH) and flies (SF) are included as outs and hit by pitchers (HBP) are excluded from the on-base percentage (OBP) calculation.

As with Estrada, this is immediately identifiable as an elite profile by the near total absence of numbers over 100, which indicate harder than league average BIP authority. Arrieta did allow higher than MLB average production on fly balls (.216 AVG-.541 SLG), for a 112 unadjusted fly ball Contact Score. This was largely due to some vulnerability in Wrigley’s soft spot in left center field; adjusted for context, Arrieta’s fly ball Contact Score plummets to 67. He allowed well below average production on both liners (62 Unadjusted Contact Score) and grounders (56), and despite somewhat significant contextual adjustments toward league average, his Adjusted Contact Scores on both liners and grounders remain excellent at 87 and 77. Those figures ranks second and first in the NL, respectively.

On all BIP, Arrieta’s combination of strong frequency and authority measures give him a 73 Adjusted Contact Score, best among NL ERA qualifiers, beating out his closest competitors, Zack Greinke, Shelby Miller and Tyson Ross. Without the contextual adjustments, Arrieta’s Unadjusted Contact Score would rank second behind Greinke, who allowed markedly louder authority on liners and grounders. Add back the Ks and BBs, and his “tru” ERA of 2.24 is right there in the mix with his actual ERA (1.77) and FIP (2.35).

How does Arrieta’s raw velocity allowed on each BIP type measure up with his NL peers? His average fly ball velocity allowed was 86.8 mph, over two standard deviations below the NL average, and second lowest among ERA qualifiers to Clayton Kershaw. His average liner velocity allowed was 89.6 mph, over two standard deviations below the NL average, and second lowest among ERA qualifiers to Francisco Liriano. His average grounder velocity allowed was 82.4 mph, over two standard deviations below the NL average, and lowest among ERA qualifiers. His overall BIP velocity allowed was 84.9 mph, over two standard deviations below the NL average, and tied for lowest among ERA qualifiers with Kershaw. Arrieta was the only 2015 ERA qualifier in either league to allow average velocities over two standard deviations below average across the board, in all BIP categories.

Where does Arrieta go from here? First, obviously to the NLCS, and then possibly the World Series. After that, his newfound status as an ace seems fairly secure for at least the intermediate future, barring injury. His excellence in a multitude of areas — bat-missing, free pass-minimizing, plus elite frequency and BIP authority profiles — means that attrition in any one area doesn’t materially damage the overall package. For my money, Kershaw and his 2.17 “tru” ERA in a few more innings would still get my Cy Young first place vote, but Arrieta is a very close second, and an eminently worthy recipient should he win the award. Right now, Cubs fans should take heart in the fact that he is sitting at home and will be on full rest for the NLCS, while every other surviving club needed to weather a Game 5 showdown.