Manchester City manager Pep Guardiola said he will make the right decision for Joe Hart if West Ham United opt not to sign the goalkeeper on a permanent deal.
Hart's future is uncertain as he nears the end of his loan, with West Ham manager David Moyes insisting no decision will be made until the end of the season.
The 31-year-old has a year left on his City contract but has little chance of re-establishing himself as their No. 1 after Guardiola decided to send him out on loan, first to Torino last season and now to West Ham.
"I think that was the toughest decision I've made since I was a manager," Guardiola said after City defeated West Ham 4-1 on Sunday. "He was an incredible professional when we were together, and there are no doubts about his quality.
"But I am here to make decisions -- sometimes good, sometimes not. We will find out in the future. He's our player and, if he does not continue here next season, we will talk. We are going to speak with the club and will take the right decision for him."
Leroy Sane, Gabriel Jesus and Fernandinho were on target, and Pablo Zabaleta scored an own goal against his old club, as City cruised to a record-equalling 30th victory of the season.