https://www.si.com/mlb/2017/10/29/world-series-baseballs-leather-justin-verlander-yu-darvish-ken-giles-kenley-jansen?utm_campaign=si-mlb&utm_source=twitter.com&utm_medium=social&xid=socialflow_twitter_si
The pitching staffs on both teams are complaining that the balls provided by MLB for the World Series are notably slicker and they're having trouble with their command. The data and metrics also suggest this, it seems to have affected the slider more than any other pitch. Tom Verducci confirmed that the balls feel different. We are seeing a lot more hanging breaking balls this series than either pitching staff has tended to throw over the course of the year on average. Some of that most assuredly has to do with nerves, but considering both staffs, and their pitching coaches, have stated the same thing about the balls, it's likely there is a factor here.
The pitching staffs on both teams are complaining that the balls provided by MLB for the World Series are notably slicker and they're having trouble with their command. The data and metrics also suggest this, it seems to have affected the slider more than any other pitch. Tom Verducci confirmed that the balls feel different. We are seeing a lot more hanging breaking balls this series than either pitching staff has tended to throw over the course of the year on average. Some of that most assuredly has to do with nerves, but considering both staffs, and their pitching coaches, have stated the same thing about the balls, it's likely there is a factor here.