clock menu more-arrow no yes

Filed under:

Statistical Comparison of 2018 ALCS Teams, the Houston Astros and Boston Red Sox

New, 2 comments

How do the Astros and Red Sox stack up? A look at the numbers.

MLB: Houston Astros at Boston Red Sox Paul Rutherford-USA TODAY Sports

It’s fitting that the 2018 ALCS comes down to the Red Sox and the Astros. By most any measure these are the two best teams in the American League. The Red Sox had the best record in the AL at 108-54, the Astros were second at 103-59. The Astros had the best Pythagorean record, 109-53, the Red Sox second, 103-59.

The following is a basic statistical comparison between the Astros and Red Sox. We will look at season hitting, last 30 day hitting, season pitching and last 30 day pitching broken down between starting and relieving. Then we will look at individual hitting and pitching statistics, season, 30 day and ALDS.

First, season hitting.

Astros and Red Sox season hitting statistics

Team/ Season Hitting Runs run differential BA OBP SLG wRC+
Team/ Season Hitting Runs run differential BA OBP SLG wRC+
Astros 797 263 .255 .329 .425 110
Red Sox 876 229 .268 .339 .463 110

Although the Red Sox have scored more runs, and have a slightly better slash line, when you adjust for ballparks, as wRC+ does, then the Astros are Red Sox are relatively equal in hitting.

Next, let’s compare their 30 day hitting stats. Of course, each playoff series is like a new season, but 30 day stats show the most recent trend line before the playoffs.

Astros, Red Sox 30 day hitting

Team/ last 30 Hitting Runs BA OBP SLG wRC+
Team/ last 30 Hitting Runs BA OBP SLG wRC+
Astros 124 .246 .330 .400 105
Red Sox 132 .264 .345 .426 106

This chart indicates that heading into the playoffs both teams slowed somewhat, and both to about the same extent.

Next let’s examine the pitching staffs. Here, the Astros display clear superiority, and even more so towards the end of the season.

First, overall pitching for the entire season.

Astros, Red Sox overall pitching, whole season.

Team Overall Pitching/Season runs ERA FIP xFIP BB% K%
Team Overall Pitching/Season runs ERA FIP xFIP BB% K%
Astros 534 3.11 3.23 3.36 7.4 28.5
Red Sox 647 3.76 3.82 3.92 8.3 25.3

The Astros were first in team ERA in the AL, the Red Sox fourth. The Astros surrendered more than half a run fewer runs per game than the Red Sox, and this superiority was supported by peripheral stats as well.

Next, let’s look at the last 30 day stats.

Astros and Red Sox overall pitching, last 30 days of season

Team Overall Pitching/30 day runs ERA FIP xFIP BB% K%
Team Overall Pitching/30 day runs ERA FIP xFIP BB% K%
Astros 80 2.99 3.40 3.59 8.5 27.6
Red Sox 123 4.69 4.51 4.42 9.9 24.7

Whereas the Astros ERA dropped towards the end of the season, although by outperforming peripherals, the Red Sox staff appeared to wear out, giving up almost a run more than its season average, and almost two runs more than the Astros at the end of the season.

Next we will compare the starting pitchers of both teams, starting with their season performances.

Astros, Red Sox starting pitching, whole season

Team Starting Pitching/season ERA FIP xFIP
Team Starting Pitching/season ERA FIP xFIP
Astros 3.16 3.28 3.37
Red Sox 3.77 3.80 3.83

These statistics look very similar to the overall pitching statistics of both teams.

Next let’s compare the season bullpen statistics of both teams.

Astros, Red Sox season relief pitching statistics

Team Relief/season ERA FIP xFIP
Team Relief/season ERA FIP xFIP
Astros 3.03 3.14 3.33
Red Sox 3.74 3.85 4.05

Again the Astros enjoy an advantage over the Red Sox, their bullpen surrendering almost 3/4’s of a run less per nine innings than that of the Red Sox.

Now let’s look at the last 30 day starting pitcher statistics of both teams.

Astros, Red Sox last 30 day starting pitcher statistics

Team starting pitching/30 day ERA FIP xFIP
Team starting pitching/30 day ERA FIP xFIP
Astros 2.86 3.15 3.52
Red Sox 4.35 4.35 3.97

Again we find that the Astros pitchers improved by season end, although the high xFIP indicates some home run luck, whereas the Red Sox starters got worse.

Next we will examine the last 30 day bullpen statistics, and this is where we will find the biggest separation between the two teams.

Astros, Red Sox last 30 day relief pitcher statistics

Team Relief/30 day ERA FIP xFIP
Team Relief/30 day ERA FIP xFIP
Astros 3.18 3.75 3.69
Red Sox 4.98 4.65 4.79

Here we find that the Red Sox bullpen in the last 30 days gave up almost 2 runs per nine innings more than the Astros and well more than one more than their own season average. It should be noted that the Astros ERA in the last 30 days significantly outperformed peripherals.

Following are season hitting statistics for the Red Sox and Astros respectively.

Red Sox. The ALDS roster is the third chart below.

The Red Sox offense is mainly supported by two MVP candidates, slugging J. D. Martinez, and Mookie Betts, and two others, Andrew Benintendi and Xander Bogaerts. After these four there is considerable drop-off.

Now let’s look at their September performance with an eye towards who’s hot and who’s not heading into the ALCS.

Two players come into post season riding a wave; Tzu-Wei Lin and Brock Holt. Benintendi is one of the core hitters who enters the playoff in a slump as does another starter, Ian Kinsler.

Next the playoff statistics against the Yankees in the ALDS.

Brock Holt, in his one game, hit for the cycle against New York. Mookie Betts had a poor series, which we can only hope continues against the Astros.

The following is the season pitching statistics for the Red Sox. The ALDS roster is three charts below.

Next the September pitching statistics for the Red Sox

The two hottest pitchers going into the playoffs appear to be Steven Wright and Nathan Eovaldi. Craig Kimbrell is near the 4 mark in ERA and Rick Porcello almost 4.5.

Following are the Boston pitching statistics for the ALDS.

Readers of this website are generally well-informed about the season and recent performance of the Astros players. If you want to take this opportunity to review the statistics, go here and here.

Let the games begin. First pitch of Game one ALCS is 7:09 CDT tonight.