Despite his strong offensive year, Aaron Rowand’s secondary average this season was just .288, 43rd best among the 75 National League players that had at least 500 plate appearances. That was especially surprising to me given his .515 slugging percentage — his secondary average was lower than Shane Victorino’s. Someone needs to get to the bottom of this and I’m here to help.

The Phillies were a tremendous offensive team in 2007, which can be demonstrated in a bunch of different ways. One of them is this: among NL players with 500 plate appearances this season, the Phils had four players in the top 20 in secondary average:



Player


SECA


NL Rank

Howard

.520

1

Burrell

.487

3

Rollins

.352

17

Utley

.343

19

Fantastic. Way to go, fellas. Alert the press. Would probably be even better if we knew what secondary average actually was or understood what it meant. A moment, please, and I’ll give it my best shot.

Another way to demonstrate that the Phillies were a fantastic team is this: among the NL players that had 500 plate appearances, the Phillies had four of the top 20 players in slugging percentage.



Player


SLG


NL Rank

Howard

.584

4

Utley

.566

6

Rollins

.531

15

Rowand

.515

18

Five good offensive players, but the lists aren’t the same. Burrell was third in the league in secondary average and not in the top 20 in slugging (he was 21st). Howard dominated the league in secondary average, but three players posted a higher slugging percentage. Utley’s slugging percentage was way better than his secondary average and you have to look hard to find Rowand’s secondary average (43rd of 75 NL players with 500 PA) despite that fact that he was 18th in the league in slugging.

What secondary average is is easy. Secondary average is TB-H+BB+SB-CS/AB.

Understanding what it means isn’t quite so easy, but secondary average measures a player’s offensive contribution. Players that walk a lot and get a lot of extra-base hits have high secondary averages. But players that have high slugging percentages don’t necessarily.

Singles hitters, especially ones that don’t walk or steal bases, get hammered. Singles don’t help your secondary average, but, unlike slugging percentage, walks do. For example, a player that is 10-for-10 with ten singles and no walks or stolen bases has a slugging percentage of 1.000 and a secondary average of .000.

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