Manchester United winger Nani views Arsenal as a bigger title threat than Chelsea this season.
The Gunners visit Old Trafford on Monday looking to consolidate top spot in the Barclays Premier League table. For their part, United know a home win would allow them to jump back to the summit, while retaining a match in hand following the postponement of last week's visit to Blackpool.
It promises to be a feast of football, with Nani believing it represents the acid test of United's trophy ambitions.
"Arsenal are a bigger threat than Chelsea now," he said.
"Chelsea have lost a few games and drawn some and their confidence looks a bit low.
"But Arsenal have been winning and being top of the league gives you great confidence."
The north London giants have lost three times on home soil this season.
However, away from the Emirates they have been a formidable force, managing recent victories over Manchester City, Everton and Aston Villa, none of whom United were able to beat on their own travels.
"Arsenal have been doing well. They are growing up in the way we are," the Portugal star said.
In Samir Nasri, the Gunners boast a player who is at the very top of his game and arguably the most influential in the top flight at present.
"Nasri is the most important player in the Arsenal team," said Nani.
"He is a very big danger for us and we have to take care of him."
Arsenal might well feel the same way about United's confident winger.
It was Nani's direct running that got Arsene Wenger's side into a flap on their most recent meeting in January as United extended an unbeaten run against Arsenal to four games in very impressive style.
"I like to play against Arsenal," he said.
"It is good playing against any big team but I have done well against them in the past.
"The way they play gives you a chance to show your quality."
It will represent the first time United have engaged in league combat since putting seven past Blackburn almost a fortnight ago, a result Nani feels signifies the Red Devils are in rude health once more.
"Our momentum is growing," he said.
"Players like Wayne Rooney and Anderson are starting to play fantastically again.
"It is great because our next two games are going to be very important for us.
"If we win against Arsenal and Chelsea we will be in a very good position to win the league."