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Trying To Make Heads or Tails of the Bullpen

It seemed like the bullpen was a strong point for the Royals in the first few games, but it has not performed as well recently. Here is a look at how the bullpen has performed in the last 7 days compared to the games before that. (I had to look at the last 7 days because I could only find one place that split out starters and relievers by date and they only did by the last 7, 14, and 30 days.)


First, here is a look at some stats:


Dates IP BB % BB/9 K% K/9 R/9 WHIP K/BB LOB%
3/31 to 4/12 40 7.5% 2.9 13.9% 5.4 3.38 1.55 1.85 75.8%
4/13 to 4/19 18.7 16.7% 7.2 20.0% 8.7 5.29 1.76 1.20 67.6%


The two number that really jump out to me is the change in walk and strikeout rates. The number of strikeouts has gone from 5.4 K/9 to 8.7 K/9 or and increase 3.3 K/9. I would generally he happy if the teams BB/9 didn't jump 4.3 BB/9 (2.9 BB/9 to 7.2 BB/9). It is nice to see the bullpen striking out one batter per inning, but when you walking a almost one batter also, the results won't be good. The K/BB ratio over the last seven days for the bullpen has 1.2 K/BB. Heck, Kyle Davies (2.00 K/BB) and Sean O'Sullivan (1.67 K/BB) have put up better ratios this season.


The increase in walk rate has contributed to the bullpen allowing almost 2 more runs per 9 innings (3.38 R/9 to 5.29 R/9) in the last 7 days then they did early on in the season. Another factor that helped to lead to lower runs allowed earlier on was that the strand rate was 75% and has since dropped to 67%.


The bullpen is always going to seem like it is struggling if it continues to put up a K/BB of 1.2. Our bullpen last season was at least able to put up a K/BB of 1.88. Until K/BB begins to approach 2, there is going to be many more nail biters like last night.