Arsene Wenger believes Manchester United are running out of steam and could be caught at the top of the Premier League.

Liverpool's stunning 4-1 victory at Old Trafford has given renewed hope to the chasing pack and Wenger believes United are starting to show signs of fatigue as the run-in approaches.

Arsenal are unlikely to catch the leaders even though their 4-0 win over Blackburn on Saturday moved them level on points with Aston Villa in fourth place.

They are still 13 points behind United, yet the games are starting to pile-up for the champions who are only four ahead of Chelsea and Liverpool.

The defeat at Old Trafford was United's 19th game this year and Wenger said: "For big spells in the game Manchester United dominated but they made mistakes on the day that usually they don't do.

"Some players looked a bit mentally tired. It opens up the race for the title, even though I still believe that Manchester United are in a strong position with the game in hand that they still have.

"They have played many matches since Christmas and it looked to have caught up with them on Saturday."

Former Liverpool skipper Phil Thompson also believed that Sir Alex Ferguson's team could blow their lead.

He said: "Manchester United look as though they are cracking up.

"Defensively, United have been so strong, but there were already signs of chinks in the armour in midweek against Inter Milan."