If that video seems eerily familiar it's because Grayson Allen tripped up a Louisville player earlier this month as well. This time it was against Florida State and he tripped their star Xavier Rathan-Mayes.
Allen wasn't getting a whole lot of calls from the refs despite getting pretty banged up, but that's just no reason to trip a guy so blatantly like that. Coach K needs to take some sort of action considering this is the second time in the last month.