Sir Alex Ferguson is preparing to send young strikers Federico Macheda and Mame Biram Diouf out on loan in January after being concerned at how their fitness levels compared to the Crystal Palace players in midweek.
Ferguson believes there is a "big problem" with the lack of real competitive football in the reserves league and that loan spells may be the answer.
Palace beat a second-string Manchester United side in the Carling Cup quarter-finals and Ferguson said: "The problem is the type of reserve league we have now - it's really a youth league, and that is a big problem.
"It [the defeat] bothers me in the sense that the level of training we do was let down. For us it was Rafael's first game, Darron Gibson's first game, Mame Diouf's only played four games this season, Macheda only his third game.
"That's not enough football to play in the quarter-final of a League Cup I'm afraid. That caught us and I was surprised of the level of fitness of Crystal Palace against us. In terms of match play we were certainly short."
Asked about the players going out on loan, he added: "It works well for all young players to get game time and that's what we are looking at for Macheda and Diouf. They need game time, there is no question about that. Every young player wants to play and we have to give them that opportunity."