Birmingham, England: Aston Villa beat nine-man Chelsea 1-0 in an English Premier League game that saw manager Jose Mourinho sent to the stands in the closing stages on Saturday.
That win saw Villa claim their first back-to-back league victories in four years as they climbed into the top half of the table.
Villa manager Paul Lambert said it was the best win of his tenure since he joined the club in 2012.
"That's probably the best win we've had. It was a fantastic all round team performance," said Lambert.
A week after securing a 4-1 win over Norwich, the Midlands club welcomed the league leaders to Villa Park, with Mourinho's men looking to restore a nine-point advantage at the top of the table.
After Manchester City had earlier beaten Hull City 2-0 away from home, the onus was on the Blues to extend their lead at the summit.
Visiting Chelsea thought it took the lead in the 41st minute when midfielder Nemanja Matic poked home from close range following a corner, however he was alleged to have handled the ball first.
The second half sprung to life after Chelsea midfielder Willian was sent off in the 68th for two bookable offences.
Referee Chris Foy's decision handed Villa the incentive, and they eventually capitalized through Fabian Delph.
The midfielder converted in the 82nd minute with a masterful flick, denting Chelsea's title surge.
Chelsea then found themselves down to nine men when midfielder Ramires was then shown a straight red in second-half stoppage time for a wild lunge at Karim El Ahmadi. That sparked animated scenes on the touchline, which eventually led to Mourinho being dismissed for his remonstrations.
After the game the Chelsea boss refused to comment on referee Foy's performance citing a fear of bringing the game into disrepute, which he intimated could lead to him facing a suspension.
"A good solid performance against a good team. Defensively we were really, really strong. We had no problems to cope with the danger that Aston Villa had and after that I prefer not to comment because I don't want to bring the game into disrepute. I don't want to be accused," said the Stamford Bridge boss.
Defeat leaves Chelsea at the top of the table on 66 points, six ahead of second-placed Manchester City, although Manuel Pellegrini's team have three games in hand.
Both Liverpool and Arsenal can close the gap to four points with wins over Manchester United and Tottenham, respectively, in Sunday's matches.