Former Manchester United defender Gary Neville says the tempo with which David Moyes' side are playing is affecting their start to the season.
The weekend draw against Southampton means United have won just three of their opening eight games in the defence of their Premier League title.
While United showed improvement from the defeat to West Bromwich Albion in their last league outing at Old Trafford, Moyes' side remain pedestrian in attack and Neville says a lack of urgency in the final third is making them easy to play against.
"Manchester United's performance against Southampton was much better than their last home match against West Bromwich Albion," Neville wrote in the Daily Mail.
"But there is still a sense that David Moyes is finding out about his players and his own way in the job. The key for me is that the speed of their game through the midfield is not quick enough.
"United have always been about those relentless waves of attacks, sustained for good periods without counter, which would eventually overwhelm the opposition.
"Because this isn't happening opponents have time to rest and recover between attacks," he added.
"And it means teams are perhaps playing a few more attacking players against United and going into games with a bit more confidence than usual.
"Southampton certainly showed that in the first 20 minutes of the game.
"I have no doubt that David Moyes will be an excellent United manager. But for now he is having to endure some painful results."
Adam Lallana's late equaliser snatched a deserved point for Southampton, who remain above United in the table and pilled on the misery for Moyes, who has begun the daunting task of succeeding Sir Alex Ferguson in uncertain fashion.
Moyes has much of the squad available to him which finished 11 points clear and claimed a 13th league Premier League title last season but is unable to replicate results.
"Sir Alex Ferguson has a great history and his experience will always work in charge of any team," said Moyes.
"But the fear comes from the team on the pitch.I am disappointed because we wanted to get a bit of momentum going and we weren't able to do that.
"We had the opportunities to get the game finished off. I am disappointed to lose a goal so late on."