Updated at 18.20

PREMIER LEAGUE LEADERS title rivals Arsenal played out a feisty goalless draw at the Emirates Stadium with much of the discussion centring on four penalty shouts all turned down.

The most prominent involved David Ospina’s clumsy first-half collision with Oscar in a keenly-contested stalemate that saw Cesc Fabregas booed on his return to his former club and Jose Mourinho maintain his unbeaten record against Arsene Wenger.

With Diego Costa and Loic Remy injured, Oscar began as the figurehead of Chelsea’s attack and was central to the game’s biggest talking point as he nodded a header past the onrushing David Ospina.

However, the Brazilian was pole-axed by the Arsenal goalkeeper and, after the effort was cleared away by Hector Bellerin, Chelsea’s frustrations were clear as referee Michael Oliver opted against awarding a spot-kick and brandishing a possible red card.

Didier Drogba replaced Oscar at half-time, who was then taken to hospital with a suspected concussion.

Fabregas then irked the home fans on his first Emirates appearance since leaving for Barcelona in 2011 when he was booked for a perceived dive in the area as a traditionally fiery contest began to heat up.

The London derby struggled to reach the boil after the break, however, despite plenty of attacking intent on show, as Arsenal moved level on points with second-placed Manchester City.

Chelsea, who extended their unbeaten run against Sunday’s hosts to eight matches, can no longer win the title at Leicester City on Wednesday, but remain well on course – 10 points clear with a game in hand.

Originally published at 17.12

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