Chelsea’s Willian reacts after scoring a late winner.

Willian struck an 89th-minute winner as Chelsea beat Everton 1-0 last night but the Premier League leaders could face disciplinary action once more after Branislav Ivanovic appeared to headbutt James McCarthy.

The flashpoint occurred after Nemanja Matic thought he had scored four minutes from time, only for the deflected strike to be ruled out for offside against Ivanovic, who had blocked the view of Everton goalkeeper Tim Howard.

Tempers flared when Gareth Barry then tripped Willian, earning a second yellow card, and Ivanovic motioned his head towards McCarthy in the resulting fracas.

The Everton substitute was booked for his part in the melee, but Ivanovic avoided censure from referee Jonathan Moss and could face retrospective action from the FA.

There was still time for Willian to net after Howard was unconvincing in clearing a cross as Chelsea remained seven points clear of Manchester City.

The champions and Sergio Aguero rediscovered their touch as they turned on the style in the second half to win 4-1 at Stoke City.

Aguero struck twice as Manchester City won for the first time in five Premier League games to keep some pressure on Chelsea at the top of the table.

Aguero’s first strike in six games since returning from injury was cancelled out by Peter Crouch before the break but he grabbed a second from the penalty spot after James Milner had put City back ahead.

Samir Nasri claimed the fourth with a fine strike late on.

The first half was a compelling affair but both sides might have had more than a goal apiece after efforts were ruled out at each end.

Crouch was first denied by an offside flag and Aguero had what would then have been his second chalked off in confusing circumstances on the stroke of half-time.

Handball was the offence, although it was only the faintest of touches and possibly not deliberate. But City reacted well to the controversy and finally showed some champion quality after a disappointing few weeks by running in three second-half goals.

Elsewhere, Manchester United cut out the long-ball tactics but they still had to battle their way to a 3-1 win over Burnley at Old Trafford.

Chris Smalling scored 22 seconds after his introduction to put United ahead and the substitute put United 2-1 up after Danny Ings’s spectacular diving header.

Burnley, whose team cost a fraction of Louis van Gaal’s star-laden XI, had United on the ropes at times in the first half and comedy defending from Smalling and Ander Herrera should have resulted in an equaliser, but keeper David de Gea saved the Red Devils once again.

Finally, Robin van Persie put the game to bed with an 82nd-minute penalty after Angel Di Maria was fouled in the box.

Manchester United leapfrogged Arsenal and Southampton into third in the table after the latter drew 0-0 at home to West Ham United, who had goalkeeper Adrian sent off.

Summaries

Chelsea 1
Willian 89;
Everton 0

HT: 0-0. Att: 41,592.
Red card: Barry (E) 88.

Man. United 3
Smalling 6, 45; Van Persie 82 pen;
Burnley 1
Ings 12;

HT: 2-1. Att: 75,356.

Southampton 0
West Ham 0

Att: 31,241.
Red card: Adrian (WH) 62.

Stoke City 1
Crouch 38;
Man. City 4
Aguero 33, 70 pen; Milner 55; Nasri 76;

HT: 1-1. Att: 27,011.

C. Palace 1
Campbell 71;
Newcastle 1
Cisse 42;

HT: 1-1. Att: 25,118.

West Brom 2
Ideye 60; Berahino 74;
Swansea City 0

HT: 0-0. Att: 23,516.