My opponent had a 400+ combo, not infinite but very long. While all the triggers were resolving, for some reason the opponent's timer stopped and my timer started. I did not have any choices to make and could not to anything, but my timer ran out. Then opponent attacked me and I could not block because my timer was out, so I lost - otherwise I would have won.
Extremely annoying because I was enduring through several minutes of a giant combo only because I knew I would win the turn after.