Wayne Rooney believes Manchester United would be "crazy" not to sign Gianluigi Donnarumma amid their goalkeeping struggles.

Donnarumma has seemingly confirmed he is leaving Paris Saint-Germain after being left out of the side by Luis Enrique for their Super Cup win and their opening Ligue 1 game.

PSG won both games, with new goalkeeper Lucas Chevalier making a save in the penalty shootout of the Super Cup to help them beat Tottenham.

Now, Donnarumma has been linked with a move to both United and Manchester City, who are reportedly the favourites, with Ederson in talks to join Galatasaray.

However, United's goalkeeper situation has been called into question. Andre Onana came under fire for his performances last year. Altay Bayindir, who started in their Premier League opener due to the Cameroonian's injury, was deemed to be at fault for Riccardo Calafiori's winning goal from a corner.

Rooney insists United should be looking to bring in a goalkeeper and thinks Donnarumma would be the perfect fit.

"Yeah, I think it has to be," Rooney said when asked if that should be a focus on the Wayne Rooney show.

"I go back to when we [United] had Roy Carroll and Tim Howard in goal. I don't think there was 100% trust from the defenders in front of the two goalkeepers. But the minute [Edwin] Van der Sar comes in and calms everything down, the defenders trust him a lot more.

"[Andre] Onana's come in, he's a fantastic keeper, but he certainly didn't fill us with confidence last season.

"Donnarumma is 26, he's one of the best keepers in the world, it'd be crazy if Man United don't go for him. I don't think he's a risk."

Last year, excluding penalties and own goals, Donnarumma conceded 24 Ligue 1 goals from shots with an expected goals on target (xGoT) value of 21.1.

That effectively means he conceded 2.9 goals more than anticipated based on the strength of his opponents' finishing.

Onana, by comparison, conceded 40 goals from shots with an xGoT value of 41.3, conceding 1.3 goals fewer than expected.

However, Onana faced 128 shots on target, 55 more than Donnarumma (73) did during PSG's title-winning campaign.

The Italian also kept just four clean sheets in the league, compared to nine for United's number one.