"The meeting today, thinking that could be the last one with Coach Coughlin there - it was tough," Manning said Monday, according to Lorenzo Reyes of USA Today.
"He has been a great coach to play under. We have a great relationship and great trust, and I appreciate the way he works, I think he appreciates the way I handle my business to play quarterback and get ready. We've had a good run. It could've been better, obviously, but I appreciate everything he has done for me."
Though Coughlin's teams have now finished below the .500 mark for three consecutive seasons, Manning puts the responsibility on himself and the rest of the players.
"He has done a great job and he definitely has not failed," Manning added. "I feel that we as players, we failed him by not playing to the level that we could."
Coughlin has not addressed his future with the Giants, but rumors have swirled that the NFL's oldest head coach will decide to retire.