Alex Ferguson has described Arsenal manager Arsene Wenger's comments over Manchester United's stamina as "petty" after his side conceded two late goals in their 2-1 defeat in London last weekend.
Arsenal scored twice in the last 10 minutes at home on Sunday to snatch victory and keep United's lead in the Premier League to six points over Chelsea.
Ferguson admitted his side has shown a tendency to let in late goals on occasions this season but dismissed Wenger's theory, expressed by Arsenal midfielder Mathieu Flamini, that it was down to tiredness.
"In the game against Arsenal, (was it) a lack of concentration? 'Yes'," Ferguson told reporters today. "From a winning position we were all gutted. It was disappointing but in terms of the stamina side of it, it's absolute nonsense.
"I thought it was a bit petty, coming out with that nonsense. There's absolutely no evidence. In terms of endurance and that kind of thing, we are well in control of that."
Asked why Wenger might have made his remarks to his team, Ferguson said: "I'm not sure. I think it's maybe making him look great again. 'I'm the great Arsene Wenger'.
"If they'd lost the game 1-0 what could he have said? Which they should have done."
However, Ferguson stressed that he does not wish to see a repeat of last weekend's late slip-up during the title run-in and believes his side may need to be more ruthless.
"I think last Sunday was a final warning for us in that respect because we are getting to the tricky time of the league...if we are winning 1-0 with nine minutes to go in the next few games, it (losing) won't happen again," he said.
Ferguson was also quick to kill speculation linking winger Cristiano Ronaldo with a possible move to Real Madrid, saying: "There's no way Ronaldo is leaving, absolutely no way."
United switch their attention on Saturday to a fourth-round FA Cup tie against Portsmouth at Old Trafford.
Ferguson has a fully fit squad but plans to make no more than a couple of changes to his first-choice side as United look to keep alive hopes of a domestic league and cup double.