The striker has scored vital late goals in his team's last three league games, earning him the moniker of Reading's super sub.
McDermott insists Le Fondre is good enough to star for his team for 90 minutes, however, and even believes the Stockport-born hitman is capable of playing for England.
"I spoke to Ray (Lewington, England assistant) this morning, he was at the game last night and I don't see any reason why Adam Le Fondre can't play for his country," McDermott told TalkSPORT.
"He finishes when he gets a chance. He couldn't have been under any more pressure there but he produced. I'm not saying he can only score from the bench, I would never ever say that.
"I'm not picking Roy Hodgson's team, but I would say Alfie (Le Fondre) could score for England from the bench or score for any team. His record is phenomenal."