by Amar Azam, at Stamford Bridge

Old foes Jose Mourinho and Arsene Wenger renewed rivalries like only then can in an explosive encounter between their sides at Stamford Bridge yesterday.

Mourinho’s Chelsea, as we’ve seen on so many occasions in the past, came out on top against their London rivals, though the fallout will linger for some time.

Eden Hazard struck a first-half penalty kick for his side, before Diego Costa scored late on to seal the win for Chelsea as the west Londoners ensured that they went into the international break remaining at the Premier League summit.

Both managers, however, will find themselves in trouble with the Football Association after tempers flared between them in the first half, resulting in Wenger shoving his opposite number in the chest before Mourinho retaliated.

“I went out of my technical area because I wasn’t happy with the challenge and I wanted to see what happened,” said Wenger. “Someone stood in front of me and that was it. I say absolutely nothing else on that.”

Mourinho acknowledged that he had “done many wrong things in football,” but refused to take any blame. Either way, a reprimand by the FA is expected.

Arsenal were humiliated when these two teams last met and no doubt Wenger used that 6-0 defeat in March to motivate his players heading into this match.

For a while, it seemed to work as the visitors began the match confidently. However, it all fell away when Chelsea took control.

Midway through the first half a reckless challenge by Gary Cahill on Alexis

Sanchez caused sparks between the rival benches. A few minutes later, however, Chelsea were ahead.

Hazard put his side into the lead with a spot-kick that he won on 26 minutes when he surged beyond two players before being fouled in the penalty area by Arsenal’s Laurent Koscielny. He easily put the ball beyond goalkeeper Wojciech Szczesny.

The Premier League’s policies on head injuries will again come under scrutiny after Chelsea’s medical team allowed goalkeeper Thibaut Courtois to continue after he was left concussed following an accidental clash with Sanchez on 11 minutes.

He left the field of play, despite having played on for more than 10 minutes, and was taken to hospital shortly after. Petr Cech took his place.

Arsenal showed little sign that they would be able to hit back in the second half.

Costa, who has scored eight goals in six league matches, secured the win on 78 minutes when he raced onto Cesc Fabregas’s superb pass before lobbing Szczesny.