As something of a follow up to roy's post earlier this year, I decided to take a look at the bullpen for the Braves this year. Effective usage of the bullpen can make a huge difference in a team's success. While the Braves made major moves to improve the rotation (which is now the 6th best in the majors in ERA), we never really addressed the bullpen in the offseason. To date, the bullpen has been so-so, posting a great strikeout rate but a league average ERA.

I'm going to take a look at how the Braves have been managing their bullpen using gmLI from FanGraphs. gmLI is the measure of the Leverage Index of the situation when a relief pitcher enters the game. Tom Tango, the creator of Leverage Index, describes Leverage Index as "a measure of the fire the player faces" in any given situation. Using the inning, outs, score, and number of players on base, gmLI can show us which relievers are being put into the most critical situations. Closers, for example, have an extremely high gLI; mop-up relievers will have the lowest. Overall, I was pretty impressed with our bullpen management.

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First post, so go easy on me.

A lot of hype has been surrounding the call-up of Kris Medlen. For Gwinnett, Medlen was thoroughly dominant. Check out these stats:

38 IP, 1.19 ERA (1.81 FIP), 0.79 WHIP, 10.42 K/9, 2.37 BB/9, 44.3 GB%

His first start against the Rockies, however, was somewhat disappointing. Medlen allowed five runs over only three innings, fanning three and walking five. Out of his 79 pitches, only 43 were strikes; that’s an Oliver Perez-worthy 54.43%. Obviously, the sample size is very small, but it does provide us some interesting data to play around with. Here is a graph of the pitches he threw:

via img195.imageshack.us

Clearly, Medlen showed three distinct pitches. He’s throwing a fastball around 87-88 mph, a changeup that is hovering around 80 (although that seems to be the least defined pitch speed-wise), and a 77 mph curve. The fastball only went for a strike only 51% of the time, which is fairly worrisome. The changeup was equally inaccurate; only 7 of 15 changeups were strikes. Medlen’s curveball had a vertical break of -4.83 (for reference, Javier Vazquez averages around -5.05) and he was actually throwing it for strikes (12 out of his 15).

Thoughts?

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