The Red Devils are in the process of negotiating a new contract with their veteran goalkeeper.
De Gea, who was close friends with Herrera when the latter was a United player, may have confided in his ex-teammate about his future.
Speaking to Manchester United's Scandinavian Supporters' Club, Herrera was stated. “I think [De Gea will stay].
“I didn't ask him if he's going to sign a new contract, but I guess he's going to do it. He cannot finish his time at Manchester United, even more so when he's at a good age for a goalkeeper, when he has given the team victories in some moments of this season.
“So I have a lot of confidence in David. I speak with him almost every week, every month, and he's not worried. He has so much confidence in himself and he's going – I hope he's going – to sign a new contract."