If they are going to check pitchers between innings for foreign substances then they should make O'Neill pee in a cup after each AB and test him for Roids.
If he was running hard then he isn't very fast. He isn't very fast: https://baseballsavant.mlb.com/leaderboard/sprint_speed?year=2021&position=&team=MIL&min=10 Surprising...would have been expecting a bit more speed from him.