*Big four set for Sunday showdown*
Robin van Persie believes champions Manchester United pose a bigger threat to Arsenal's hopes of regaining the Premier League title than Chelsea.League leaders Arsenal host third-place Chelsea at the Emirates on Sunday, while second play fourth with United meeting Liverpool at Anfield.
Van Persie said: "I just think our biggest rivals at the end of the season are United, because of the quality.
"That is why I think it will be a battle between Arsenal and them."
The Gunners are three points ahead of their London rivals and just one ahead of champions Manchester United.
And 24-year-old Van Persie believes Sir Alex Ferguson's side's strength will prove decisive come the end of the season.
"United have lots of quality players up there who can win games for the team," he said.
"Even when they are playing poorly, they have Wayne Rooney, Cristiano Ronaldo and lots of good strikers who can win games.
United will knock Arsenal off the top of the Premier League should they win at Anfield and remain there if the Londoners are held or beaten by Chelsea later on Sunday.
Red Devils striker Louis Saha rates last year's corresponding fixture with Liverpool, won by John O'Shea in injury time, as one of the highlights of his career and is confident a win at Anfield can strengthen United's title charge.
"Without doubt, it is the most intense atmosphere for a Manchester United player," he said.
"I have played there a few times now but the win we had there last season was amazing. That is one of the greatest feelings I have ever had as a footballer."
"My main memory of last season is that the win at Liverpool kick-started us towards the title. It proved we were strong enough.
"We are going there much earlier in the season this time and there is still a long road ahead. But it does give us a chance to show exactly how good we are."
Dutchman Van Persie, who has recently returned from a long-term knee injury, insists a win for Arsenal is vital if the Gunners are to remain in the hunt for the the title they last won in 2004.
"We need to win on Sunday. It's not about a draw or anything else. We need to win because we are just one point clear of them. That's why we need to win."
He added: "In games against teams like Middlesbrough, you can sort of collect bonus points. You need to win those games so you can, in a worse-case scenario, lose a game against Chelsea or Man United."