Celtic goalkeeper Joe Hart has paid tribute to Sergio Aguero after he announced his retirement today.

The pair spent several seasons together at Manchester City, helping the club win its first Premier League title.

"Sad news," Hart said.

"I think goes without saying that the entire footballing world appreciates you for the player you are, everything you achieved in the game and all the smiles you put on people's faces.

"You were a great team-mate and a good friend. It is sad but I think it is important you look at all the amazing things you have done but good luck for the future, congratulations on an amazing career and stay safe."