Crystal Palace caretaker boss Keith Millen felt Ian Holloway worked himself into the ground this season.
Millen will take temporary charge of the side, starting with Saturday's visit of league leaders Arsenal, and revealed he had noticed Holloway was starting to feel the strain.
When asked if he could tell the 50-year-old was starting to tire, Millen replied: "I did yes but it is not just recently.
"When you look back at the last three or four years he has been in the play-offs and getting promoted and hasn't really had a summer off.
"When we won promotion this year he was straight in to the recruitment of new players and was pretty tired when we came back from pre-season.
"When you don't get results it does take its toll and I think the frustration of not quite rejuvenating the group was quite hard for him to accept."
