It happened at end of regulation and OT.
Baer, Bohannon, and of course, Ellingson at end of regulation. Baer and Bohannon have to run to a referee screaming timeout; the Barn is loud, the refs will be watching the ball (unless it's a good crew -- this wasn't and the Hispanic looking ref is just not good), they can't assume the ref will hear or look for them.
Same situation in OT with Baer.
The one that ticks me off is the Ellingson time out call. As soon as the ball is inbounded that close to the baseline, the baseline ref has to leave his cozy area on the far side of the basket and sprint to the ball because any kind of common sense and experience will tell him that there will be a call for timeout -- that's why the Iowa bench was livid--and who knows there might even possibly be a foul.
It was a horrible call because the ref was out-of-position -- a spectator -- and made a lazy call that may have cost Iowa the game.