Juventus goalkeeper Gianluigi Buffon cannot understand how Manchester United let Paul Pogba join them on a free transfer in 2012.
Pogba's impressive displays have seen him linked with a move away from Juve during the January transfer window, with Paris Saint-Germain said to be admirers as well as his former club United.
The Bianconeri secured his services for free 18 months ago and Buffon believes it was remiss of United to let the France international leave.
"He's one of those players who leaves you with your mouth wide open," Buffon said to Italy's Italia Uno channel. "We all asked ourselves, after seeing him train with us for the third or the fourth time, when he was still unknown, whether the people in Manchester couldn't see very well."
The French midfielder was only 19 when he arrived in Turin. He led his national team's under-20 selection to victory in the FIFA under-20 World Cup last summer.
Since then, he has moved ahead of Claudio Marchisio in the Juve midfield pecking order and earned his first senior calls for France.
United boss David Moyes was at Juventus' game at Cagliari at the weekend, where he was understood to have had an eye on Juve's midfield duo of Pogba and Arturo Vidal, and also Marchisio.
Neither Pogba nor Vidal will be leaving Turin soon though, according to teammate Giorgio Chiellini.
"I can see that everybody wants to stay here and sign new contracts," Chiellini told Mediaset. "Pogba knows how important he is for us. He's got clubs lining up for him, but he needs to keep his cool and carry on playing the way he is, in spite of the pressure.
"Vidal has only just renewed his contract, and he is one of the strongest midfielders in the world. As for [Andrea] Pirlo, we're just waiting for it to be made official, but if somebody like Andrea decides to commit himself to this project again, then that can only mean we are set to grow even more."
Juve have won 11 Serie A games in a row to establish an eight-point lead at the summit and edge closer to a third straight Scudetto.
They are also in the quarterfinals of the Coppa Italia, where they will face Roma, and will meet Trabzonspor in the last 32 of the Europa League, the final of which will be staged in their own Juventus Stadium.