Chelsea boss Jose Mourinho believes a wrongly-awarded penalty in the 1-1 draw with Southampton denied his side an eight-point lead at the top of the Premier League.

The Blues are six points clear of second-placed Manchester City with a game in-hand, but for the second successive match against Southampton, Mourinho bemoaned decisions by the match officials.

Mourinho was fined £25,000 for saying there was a "clear campaign" against his side after Cesc Fabregas was denied a penalty and booked for diving instead in the December 28 draw at St Mary's.

The Blues boss on Sunday was frustrated Nemanja Matic was penalized – allowing Dusan Tadic to score from the spot and cancel out Diego Costa's first Premier League goal for almost two months – and Branislav Ivanovic was not awarded a spot kick at the other end.

"I'm happy with the situation. I'm happy with the six-point lead, but I'm not happy with the result," Mourinho said.

"If you remember our two matches against Southampton: in one game, one penalty that is not a penalty and in another game a penalty that was not given. You are speaking about six points transformed into two points."

Mourinho was clearly upset with the penalty decisions, but bit his tongue on this occasion.

He said: "My opinion is not important. Important is Mr Mike Dean (the referee).

"His decision was a penalty and his decision was no penalty on Ivanovic."

Ivanovic may have been clipped by Tadic, but fell theatrically, dissuading Dean from pointing to the spot.

Asked about the fall, Mourinho deferred to his media officer sitting alongside, saying: "You have to control me, if not…"

Mourinho was told television pundit Graeme Souness – with whom he had a public exchange of views this week after the Scot criticised Chelsea's conduct in the Champions League exit to Paris St Germain – thought Matic had conceded a penalty.

"Graeme Souness says also that it's more a reason to criticize a player who asks for a yellow card than a player who kicks somebody in the chest," Mourinho added.

"I went to Sky and they told me their pundits said it's a penalty. I went to BBC and they told me it's not a penalty. I went to the radios and they told me it's not a penalty.

"Pundits are paid to wear my suit, but I'm not paid to wear their suit or to comment on their comments.

"If one day I become a pundit, I will wear a manager's suit. I will win every game, because pundits win every game, and then I can be critical and I can be phenomenal like they are."

Matic was replaced by Ramires soon after a second-half foul on Sadio Mane which could have seen him booked for a second time and sent off for a second successive Premier League game.

"When that penalty is given you have to believe that the second yellow card can come," said Mourinho, who referred to Ramires' sending off at Aston Villa last season.

Mourinho was pleased with his players' response to the European elimination on away goals to PSG as their grip on a first title in five years tightened after Manchester City lost at Burnley on Saturday and Chelsea drew on Sunday.

"I'm happy with the players' reaction," he said.

Mourinho feels third-placed Arsenal, who are seven points behind, are still in the title race, but does not know what to expect from the Gunners, who the Portuguese believes have an easier run-in than the Blues.

"More teams are in the race," Mourinho said.

"For me, which momentum? 3-1 against Monaco or 3-0 against West Ham? It depends on the momentum.

"If somebody tells me in August that at the end of March we are six points in front and one match in hand, I would sign immediately. No doubts."

Southampton manager Ronald Koeman was "very pleased" with his side's display.

"To get a good result against them you need luck, you need a great goalkeeper, you need great organization in a team and we had that," Koeman said.

"(I am) proud of the team. That gives a very good feeling."

The Dutchman felt Saints – for whom Mane and goalkeeper Fraser Forster starred – deserved a spot kick, but refused to criticise Dean for not dismissing Matic early in the second half.

"In my opinion it's a penalty, yes," Koeman added.

"It's difficult jobs for referees. (Matic on Mane) is a foul that maybe can be a yellow card and that means his second one.

"It's always difficult. I'm not supporting referees showing eight, nine, 10 yellow cards every game.

"In my opinion the referee did a great job today."

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