Arsenal manager Arsene Wenger believes Chelsea's "financial power" was a major factor in his side's 2-0 defeat at Stamford Bridge.
The Blues ultimately proved too strong for the Gunners on Sunday, with Eden Hazard netting a first-half penalty before Diego Costa made sure of the result late on with a well-taken finish.
Both Hazard and Costa were signed for big money by Chelsea in recent years, and Wenger was keen to make reference to that fact after the match.
"It was a very even game I think, where in moments we were a bit unlucky sometimes,'' Wenger, who almost came to blows with Jose Mourinho on the sidelines during the game, told a news conference.
"As well, at the end of the day, they have a financial power and they used it in a very efficient way when they had the chances.
"Their individual players who can make the difference made the difference -- Hazard and Costa.''
Another big-money signing of Chelsea's, Cesc Fabregas, laid on the ball for Costa's second-half goal.
Wenger, though, felt ex-Arsenal man Fabregas should have been penalised earlier in the game after blocking Jack Wilshere's strike in the penalty area.
"It was a handball,'' he said.
In a feisty encounter, Wenger also thought Gary Cahill was fortunate not to be sent off for his challenge on Alexis Sanchez and bemoaned the persistent fouls he perceived were committed by Oscar and Branislav Ivanovic.
The Frenchman, who has never beaten a Chelsea side managed by Mourinho, also felt two instances of quality made the difference.
Wenger added: "It was a very even game today. It was down to very little. Hazard and Diego Costa made the difference. It was a very intense game. We couldn't score. They did.''
Unbeaten Chelsea are now five points clear at the top of the Premier League table and nine points ahead of seventh-placed Arsenal, who were defeated in the league for the first time this season.
Regarding the points gap, Wenger added: "Of course it's a lot. We have had a lot of difficult games up to now, and with the quality of the team they [Chelsea] have it's a lot, but we will fight to come back.''