USC coach Pete Carroll was reportedly unhappy with one of the drills that NFL coaches and scouts observed his former players run through at USC’s pro day workouts this week.

According to Adam Rose of the Los Angeles Times, the players engaged in “a hand-to-hand combat drill,” and Carroll wasn’t happy to see it. Carroll reportedly said, “That won’t happen again here.”

USC defensive tackle Sedrick Ellis said of the drill, “That was a sleeper. I didn’t know that one was coming. You see it on film but you’re never quite ready for that until it happens. That drill’s a doozy, man.”

It’s unclear why Carroll was unhappy with the drill, but ultimately, pro days exist for NFL teams, not the colleges that host them, and it would be surprising if Carroll actually did something to prevent scouts and coaches from running the drills they want at future USC pro days.