Over the weekend, we saw something out of Yankee pitchers that we hadn't seen in a while. Joba Chamberlain threw a 98.1 mph fastball, not far off from his average 97.5 mph on Saturday afternoon, Ivan Nova hit 97 mph, David Robertson hit 94.9 mph, and Boone Logan 96 mph. Listening to the games on the radio, or watching on YES, John Sterling and Michael Kay drew attention to the velocity a number of times. It's quite encouraging to see such high marks in the month of April, especially when pitchers are still building strength. But I have bad news for you. The guns in the Rogers Centre were juiced. At least that's the saying, nowadays there are PITCHf/x cameras set up at three points, which are calibrated to measure everything from velocity, to acceleration, to location. The calibrations were off this weekend, and unfortunately there were some false story lines made of it.
All of Ivan Nova's 2013 pitches are plotted above, and you can see a clear jump in velocity over his last 100 pitches. In fact, Nova averaged 92.3 mph on his four-seam in his first outing, then 92.9 mph in his second outing. On Sunday, Nova was sitting at 94.5 mph, according to the miscalibrated PITCHf/x cameras, topping out at 97 mph.
There was a substantial boost in velocity for most of the Yankee pitchers, and thus far, a pitcher's four-seam has seen an average of .77 mph gain in velocity at the Rogers Centre in 2013. There's a case to be made that the dome and the slightly warmer temperatures have affected velocity, but this is a significant boost, one that's much greater than the warm dome in Tampa. (.22 mph increase in Tropicana Field) Perhaps it has something to do with the exchange rate, metric system conversion, or their use of zed, but for now you can't trust the PITCHf/x data in Canada.