Last night, it seemed the Dodgers made good contact a lot off of Delgado, as they collected 11 singles. Some have judged that the D-backs were unlucky, as the BABIP was so high, while others have figured that since there was good contact, that showed the pitcher at fault. So I went back and looked at ground ball/line drive statistics (at Baseball Reference) and while judging what is a line drive and what isn't is an inexact science, the data available backs up my thoughts: yes, the Dodgers made some good contact, but they were also extremely lucky.
In his six innings of work, Delgado gave up six line drives. All were hits. He also induced seven ground balls, three of which were hits. The other two hits were fly balls, one of which was a bloop that was almost caught by Kubel (and almost definitely would have been caught by Parra or Pollock.) So 100% of his line drives last night went for hits. Is that typical?
Line drives, as Baseball Reference figures them, are typically hits. But still, not at the 100% rate. In his other four starts this season, Delgado has given up 12 line drives, 10 of which were hits, or 83%. But the rate of ground balls going for hits was abnormally high as well. 3 out of 7, or 43%, of ground balls induced by Delgado were hits. By comparison, only 10 of 36 ground balls in his previous starts were hits, or 28%. Call it luck, or defensive placement (I think at least three hits went about three steps left of Chavez at third), or whatever, the Dodgers hot bats were helped by it.
To provide a bit of control for these numbers, I also looked at IPK's games. 23% of IPK's ground balls have been hits, which is close enough to Delgado's rate in his first four starts, although almost half of what Delgado's rate was last night. However, only 68% of line drives have resulted in hits, substantially lower than Delgado's 83% over his first four starts, and obviously much lower than last night.
In conclusion, if you give up line drives, you are going to give up hits, as we all know. But if every line drive is a hit, you had some bad luck, or some bad defensive placement, or both. 2/3 of line drives resulting in hits is probably about average, and 1/4 of ground balls resulting in hits is probably about average. Anything beyond that, and the other team either got lucky, or you need to change the defense. Last night, the Dodgers got lucky and took advantage of not having the best defensive lineup out there, and the results were obvious. But their luck has to turn eventually. Hopefully it will start to turn tonight.