Joe Hart has thanked Wayne Rooney for describing him as the best goalkeeper in the world - but says there are days he feels like the worst in the world.
Hart's sublime performances in the Champions League against Real Madrid and Borussia Dortmund prompted Rooney to take to Twitter and post a message saying Hart was the best goalkeeper in the world, ahead of the likes of Iker Casillas and Gianluigi Buffon.
Hart pulled of a string of outstanding saves to keep the Citizens in the game against Dortmund, before Mario Balotelli ensured a point from the penalty spot late on at the Etihad Stadium.
That prompted the Red Devils striker to tweet: "Have to say Joe Hart has been incredible. For me best keeper in the world."
The Manchester United striker and Manchester City goalkeeper have enjoyed their fair share of battles over the years - Hart was famously in goal when Rooney scored his overhead kick in 2011 which was subsequently voted the best goal in Premier League history earlier this year.
Hart described it as a 'special honour' to receive such praise from his Old Trafford rival - but the Manchester CIty stopper warned that the fickle nature of life in goal could shift him from hero to villain in a matter of days.
"It's a special honour for some special people to say some nice things, but we move on," Hart said about Rooney's remarks.
"In goal, you can be the worst in the world two days later."
He added: You've got to remain level-headed. If you don't, it's a big slap when you do something wrong.
"People are going to say bad things about you but that's football. You can't go too far one way or the other or you leave yourself vulnerable."
In other Manchester United news, Rooney has been talking about his relationship with his Twitter followers, and offered a warning to footballers on the social network site.
Recently, Chelsea's Ashley Cole landed himself in hot water after he posted a derogatory message about the FA, while Rooney's Manchester United team-mate Rio Ferdinand was fined £45,000 for a message he retweeted about Ashley Cole.
"It is a good way for the fans to see a different side of you, away from football," The Red Devils star said.
"But you obviously know everything you put on there is seen by everyone who follows you.
“It will be in the newspapers the next day so you have to be careful."