Arsenal manager Arsene Wenger says the EPL title is Chelsea's to lose after Arsenal were outclassed 3-1 by the Premier League leaders at Stamford Bridge.
Marcos Alonso opened the scoring in the first half, outmuscling Hector Bellerin to head home the rebound after Diego Costa had struck the bar.
The Arsenal manager admitted his side were not good enough as they fell 12 points behind the leaders.
"At the moment they look confident, powerful, strong, they don't concede goals," Wenger told reporters when asked if Chelsea would now be champions.
"It's theirs to lose, they're in the best position. They don't play in Europe, they can wait every week for the next game and prepare properly. They are in a very, very strong position."
Chelsea manager Antonio Conte hailed his transformed team, saying they were completely different from the side that lost to the same Arsenal opponents last September.
The buoyant Premier League leaders tore Arsenal apart to expunge memories of their 3-nil drubbing at The Emirates last year.
Chelsea have won 16 of their 18 Premier League games since that Arsenal defeat that had languished eighth on the table.
But Conte cautioned against believing his side had already won the Premier League.
"There are 14 games to play and there are 42 points to take," he said.
"For sure today it was important to win against a rival for the title and you must exploit it when you have this sort of situation."
Across town at White Hart Lane, Harry Kane struck from the penalty spot to give Tottenham Hotspur a 1-0 victory over struggling Middlesbrough and reduce the gap on Premier League leaders.
Spurs outclassed Middlesbrough throughout, but took almost an hour to transfer their dominance to the scoreboard when England striker Kane fired home a 57th- minute penalty after Son Heung-Min was felled in the box by Bernardo.
Middlesbrough had their chances to equalise with Alvaro Negredo firing an acrobatic scissor-kick wide with five minutes to go and Marten De Roon's injury- time shot also going close.
The win leaves Spurs, who travel to Liverpool next weekend, in second on 50 points, nine behind Chelsea and three ahead of North London rivals Arsenal, while Middlesbrough remain 15th on 21 points.
Later, Sunderland crushed fellow Premier League strugglers Crystal Palace 4-0 at Selhurst Park.
Romelu Lukaku scored after just 30 seconds, equalling the fastest goal in the Premier League this season, and went on to hammer in four as Everton beat struggling Bournemouth 6-3 amid a goal glut at Goodison Park.
Liverpool's calamitous freefall in 2017 continued with a shocking 2-0 defeat at Hull City which may have put a fatal dent in their title hopes.
West Ham United recovered from a goal down to cruise to a comfortable 3-1 victory away against Southampton.
Watford's new loan signing M'Baye Niang scored his first goal for the club in their 2-1 Premier League win over 10-man Burnley at Vicarage Road.
And James Morrison scored the only goal of the game early in the first half to earn West Bromwich Albion a 1-0 win over Stoke City at the Hawthorns.