Arsene Wenger has conceded Arsenal's Premier League title challenge is over following Wednesday's 2-1 derby defeat at the hands of Tottenham Hotspur.
Goals from Danny Rose and Gareth Bale at White Hart Lane secured a first north London derby victory for Spurs since 1999.
Nicklas Bendtner pulled a late goal back for the Gunners but afterwards Wenger admitted that his side's title chances were effectively over.
Arsenal needed to take maximum points from their final five games if they were to stand any chance of winning the league, but they look set to end another season without major silverware once again as they are six points behind leaders Chelsea with just four games to play.
"We lost a game we couldn't afford to lose in the title race," admitted Wenger.
"That shows that we're not mature enough because you can't afford to lose this type of game if you want to win the championship.
"There's too much to do now. We're very unlikely now to win the championship.
"We'll continue to fight but even a point wasn't enough from tonight – we needed three points."
The only positive on the night for Arsenal was the return of Robin van Persie from a five-month ankle injury absence.
The Netherlands striker came on as a second-half substitute for Denilson as the Gunners went for broke.
"You could see straight away he gave us something different and something special," added Wenger.
"Tottenham defended very well and we were not good enough with our final ball in the final third.
"The bad luck we've had this year is that we go into the final sprint of the season with many good players out.
"You could see tonight that it was too much for us."