That is according to former Italy forward Antonio Cassano, who has criticised Donnarumma's stunning move to Paris Saint-Germain this summer.
Donnarumma impressed for Italy this summer at Euro 2020 as Roberto Mancini's men defeated England in the final at Wembley.
The 22-year-old former AC Milan star saved penalties from Jadon Sancho and Bukayo Saka as Italy lifted the Euro 2020 title after a nail-biting shootout.
Donnarumma's superb campaign with the Italians earned him the Player of the Tournament award, as well as a place in UEFA's Euro 2020 Team of the Tournament.
The Italy No 1 left Milan at the end of last season and completed his sensational free transfer to PSG on Wednesday.
However, Cassano is not sure Donnarumma can be classed as the best 'keeper in the world if the likes of Bayern Munich, Madrid and Barcelona were not pursuing him.
The 39-year-old argued Donnarumma should have challenged the likes of Thibaut Courtois and Marc-Andre ter Stegen for the No 1 shirt at their respective clubs.
Speaking on Christian Vieria's Twitch channel, Cassano said: "Why, if he is the best goalkeeper in the world, aren't Bayern Munich, Real Madrid and Barcelona after him?
"[Manuel] Neuer is 36 years old. If he is the best goalkeeper at the moment, take on Courtois and Ter Stegen and send them away. Instead, he goes to PSG."
Donnarumma made his senior debut for Milan at only 16 and broke into the first team to establish himself as the first-choice 'keeper.
The Italian shot-stopper made over 200 appearances for Milan and lifted an Italian Super Cup with the side in 2016.
Donnarumma signed a five-year deal with PSG and is expected to challenge Keylor Navas for the No 1 shirt next season.
"I am delighted to be part of this huge club," he told the PSG's official website.
"I feel ready to take on this new challenge and continue to grow here.
"With Paris, I want to win as much as possible and to bring joy to the supporters."
Featured Image Credit: PA
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