EDITOR'S NOTE: Due to work commitments for Naveen, he is replacing his weekly recaps with a monthly recap, which should afford him more attention to detail. See more from him at the end of this post.
Runs Scored: 98 | Runs Scored per Game: 3.50 | Runs Allowed: 101 | Runs Allowed per Game: 3.61
Competition Adjusted Runs Scored: 0.86 | Competition Adjusted Runs Allowed: 0.89
The Cubs' staff pitched very well in June -- allowing 11% fewer runs than the average staff would have allowed against the competition the Cubs faced. This hasn't just been a June trend, over the course of the season:
- Cubs pitchers have surrendered the 10th fewest number of runs in the majors (344) and fewer than four playoff teams, (Angels, Orioles, Brewers, Tigers)
- Cubs starters are second in the majors in WAR (9.2), and the overall staff is third in WAR (11.1)
- Cubs pitchers has posted the fourth-best FIP (3.39) in the majors
The Three Most Important Plays
6/17 Bot 7, men at first and second with one out, 4-3 Cubs: Garrett Jones homers off Brian Schlitter to give the Marlins a 6-4 lead, resulting in a -.491 WPA. The Cubs had a 59.2% chance of winning the game prior to his at bat, and a 10.1% chance of winning the game after his at bat.
6/16 Top 6, men at second and third two outs, 3-1 Marlins: Starlin Castro homers off Tom Koehler to give the Cubs a 4-3 lead, resulting in a .440 WPA. The Cubs had a 21.3% chance of winning the game prior to his at bat, and a 65.3% chance of winning the game after his at bat.
6/16 Top 13, man on first with two outs, 4-4 Tie: Travis Wood doubles off Jacob Turner to give the Cubs a 5-4 lead, resulting in a .417 WPA. The Cubs had a 43.9% chance of winning the game prior to his at bat, and an 85.6% chance of winning the game after his at bat.
Most Valuable Cub
Arrieta posted a 0.92 ERA / 1.46 FIP / 2.07 xFIP line in June, which was good for the second best ERA, third best FIP, and fourth best xFIP in the majors. Furthermore, he posted the fourth best K-BB% (his 33.3% strikeout rate and 4.2% walk rate, led to a 29.2% strikeout/walk rate differential) in the majors. Arrieta was in the conversation with Felix Hernandez and Clayton Kershaw for June's best pitcher.
Let's take a step back and see how he got there. The results are at least partially a result of Arrieta's new approach. Arrieta is:
- using his cutter much more frequently (nearly 30% of pitches thrown versus 14% the year before)
- throwing strikes with his cutter (his ball rate on the cutter is below 30%)
- generating swinging strikes with his cutter (13.8% swinging strike rate this year versus 11.5% the year before)
While we should always be wary of small sample sizes -- as fantastic as Arrieta's six starts in June were, they spanned 39⅓ innings -- research has shown that strikeout, walk, and ground ball rates stabilize at levels that Arrieta has already surpassed this season. Thus, his career-best strikeout (28.3%), walk (6.8%), and ground ball (49.7%) rates are likely here to stay.
Least Valuable Cub
Travis Wood: In 200 innings last year, Wood posted a 2.8 WAR season, the best of his young career. Entering his age 27 season, fans could have expected 2013 to be the start of a number of above-average seasons for Wood. Unfortunately, Wood has taken a step back this year. After posting a 13.5% walk rate in June, Wood's walking nearly 10% of batters faced this season, and it's his command that seems to be the root of hist struggles this year.
If we look at PITCHf/x data, we can isolate the pitches Wood is having the most trouble commanding. Last year, Wood threw 68.2% of his cutters for strikes; this year that figures stands at 61.8%. Batters also seem to be having more success against his cutter this year -- while hitters posted a .275 wOBA against the cutter last season, they're recording a .340 wOBA this season. Furthermore, Wood's slider isn't nearly as effective as it was last season -- hitters are posting a .362 wOBA against the slider this season versus a .231 wOBA last season and aren't whiffing nearly as frequently against the slider as they were last season (9.6% versus 13.5%). Wood's ability to make adjustments to his cutter and slider will play a large role in dictating his rest-of-season performance.
Up and Comers
I've switched from writing weekly recaps to monthly recaps for the following reasons:
- Work continues to keep me busy, and often prohibits me from being able to post according to a weekly schedule
- It's difficult to read too much into the data on a weekly basis as trends (that determine the most and least valuable players) are much more meaningful on a monthly basis
- Writing monthly recaps will allow me to put some time towards interesting one-off pieces (observations on player performance, deep-dive reports on newly acquired players, etc.)