Suh failed to turn up for the session, leading to suggestions that all might not be well in his relationship with the team as he enters the final year of his rookie contract.
However, Caldwell insists that he knew about Suh's intention to miss the workouts and does not believe that it is an issue for his side.
"It certainly didn't blindside me. We certainly knew. He and I have probably had more discussions than any player that we've had on the team," Caldwell told reporters.
"He's been in and out. I think he was here on a couple days when I came on a visit, so we kind of knew exactly what was going on. But from a coach's standpoint, it's just like anything else. My business is to get in the position to win and win consistently. So we want every single minute of every single hour with every single player. That's the way we want it.
"The rules don't always lend to that type of attitude, but nevertheless that's the way it is. We had several discussions, and I told you my feelings on it and what I would like to have done, and that's just kind of the way it is at this point in time."
Suh has previously opted out of voluntary team sessions in favour of training with his own people.