While the White Sox have played a number of games with instant replay available, it's been difficult to detect any difference.
One reason is that they haven't come up that often. Another one -- when the managers have challenged incorrect calls, the umpires haven't bothered reversing them.
MLB.com has video of three calls that umpires upheld despite evidence to the contrary, with two benefiting the Sox.
On Sunday, Adam Eaton threw his body at second base on a steal attempt and went screaming past the bag. On his attempt to scramble back to second, Josh Rutledge appeared to tag him on the hand. Eaton was ruled safe, and the call was upheld.
On Wednesday, Leury Garcia fumbled the transfer from glove to hand on an attempted double play, but the original call said he didn't even catch the ball for the force. The replay showed a traditional transfer gone awry, but the call was upheld and the runner at second was safe. Between dropped transfers and the neighborhood play, double plays could be a vital replay battleground.
Soon afterward, Eaton was credited with an outfield assist at third base. It was a great throw, but old friend Jason Bourgeois appeared to get his foot on the bag before Marcus Semien could apply the tag. The call was upheld, perhaps because one cameraman failed to get the play in the frame.
It's possible the process will transform dramatically during the regular season, with two broadcasts at the ready and better ways to use those angles, but when I read articles about the system like Jeff Passan's ...
Much of that depends on how many bad calls it overturns. The league commissioned research on "clear and convincing" incorrect calls from the 2013 season and said umpires definitively blew 377. Of those, MLB said, 86 percent were either force plays (like a runner being safe or out at first base) or tag plays (steals, pickoffs and otherwise). Though this data is rather misleading – there were plenty more wrong calls, except technology did not allow the league to put a number on it – it does show that baseball could see upwards of 400 calls changed this season.
... and compare it to the calls that haven't been overturned, it makes me wonder if their standard for conclusive evidence is closer to "beyond a shadow of a doubt" than "beyond a reasonable doubt." Or maybe it's even beyond it.