George Graham warns Costa of referee clampdown

Chelsea striker Diego Costa (right) and Gabriel Paulista (centre) clash at Stamford Bridge. Picture: PA

Graham is adamant the Spain striker should have been sent off for bumping the chest of Laurent Koscielny and raising his hands to the Frenchman’s face in the first half at Stamford Bridge before Gunners defender Gabriel saw red for retaliation.

Costa could yet face Football Association scrutiny over his role in Gabriel’s sending-off. The FA will await referee Mike Dean’s report before deciding whether or not the Chelsea striker has a case to answer.

Although Costa got away with only a yellow card, Graham says referees are now likely to seek to ensure he does not escape stricter punishment in the future.

The Scot said: “I think [Costa] is going to be a targeted man now by the officials and probably rightly so.

“[Didier] Drogba was the main [Chelsea] man for nearly ten years and he was very, very physical but he didn’t take to the extremes that Costa has taken it to.

“Although you’ve got to keep that physical intensity, once you step over the mark he’s got to be dealt with by officials, it’s as simple as that – and I think he will be.”

But Graham also suggested that Arsenal manager Arsene Wenger ought to be stricter with his own players, with Santi Cazorla’s second-half sending-off taking the number of Gunners players dismissed in the Premier League to 79.

Graham added: “[Wenger] is not the most strict manager and he really needs to get hold of his own players because there’s no way he [Gabriel] should have been sent off – it’s his own stupidity that got him sent off and they’ve got to handle that.

“[But] Arsene does it his way and look at the record he has got in English football – he has been instrumental in getting a certain way of playing, the diet – he’s brought all these things and trophies as well so how can you fault him?”

Chelsea midfielder Nemanja Matic believes his side wanted to win more than Arsenal.

The Blues claimed their first home league triumph of the season and extended the Gunners’ winless league run against their rivals to eight games, courtesy of a Kurt Zouma header and late Eden Hazard strike.

“We wanted to win more than them,” Matic told Chelsea TV. “It was a very important three points for us, especially against them.

“We didn’t start the season very well so it was very important to win these two games – Champions League against Maccabi [Tel Aviv] and the derby against Arsenal.

“We didn’t concede one goal and we scored six. We have to continue to play like this, especially the next game – it’s going to be very important for us.”

Arsenal goalkeeper Petr Cech spent 11 years at Stamford Bridge and was defeated on his return with the Gunners. “You have to pick yourselves up and continue,” Cech said.

“That’s the only thing you can do because you don’t win or lose the league after five games.

“You need to carry on until the last minute of the campaign. Obviously we need to keep going.”