Chelsea extended their lead at the top of the Premier League to six points with a 1-1 draw at home to Southampton this afternoon.

Diego Costa and a Dušan Tadić penalty inside the opening 20 minutes proved to be the only goals of the game as Southampton goalkeeper Fraser Forster put in an inspired performance.

The Blues still have one game in hand on second-place Manchester City who were beaten 1-0 at Burnley yesterday.

Southampton are only the third of 14 teams to visit Stamford Bridge and take as much as a point from Chelsea this season.

Here are the major talking points from the game:

1. Chelsea ‘would have’ had a penalty if…

With the score at 1-1 in the first half and after Southampton had been awarded a penalty, Chelsea had a great shout for one themselves when Branislav Ivanović had his heel trod on inside the penalty area. Replays showed a foul on the Chelsea right-back but no penalty had been awarded.

The Serbian’s decision to throw his arms in the air unnaturally as he went down dramatically may have played its role in the decision from Mike Dean not to award a spot kick for the home side, given he had a split second to make the decision.

2. Chelsea have won the Premier League

Yesterday’s loss for Manchester City saw the Premier League leaders extend their lead to six points. The defending champions only have nine games remaining whilst Chelsea can extend their lead to nine points by beating bottom-of-the-league Leicester City.

Chelsea may have dropped off since the first half of the season, dropped points too, but Manchester City and co have failed to sustain any title challenge of their own. José Mourinho’s side’s point today puts any doubts behind them. It could easily have been three against one of the Premier League’s top sides but for the opposition goalkeeper.

3. Fraser Forster: England number 1

The Southampton goalkeeper put in an inspired performance at Stamford Bridge this afternoon with save after save in the second half to earn his side a point. Fraser Forster has kept the most clean sheets in the Premier League this season.

Eden Hazard was denied from a close range by an excellent reaction save. Smart stops also denied the likes of Loïc Rémy and Oscar who had good chances in the second half. Perhaps not commanding in the box at set pieces is one weak point of the young Englishman.

4. Regardless of Mourinho’s comments, Chelsea get decisions

Nemanja Matić started the second half on a yellow card and somehow escaped a second in the opening minute of the second half. The Serbian midfielder tripped Sadio Mané outside his own penalty area with the Saint in an excellent position. If this was against Chelsea there’s no doubt we’d be hearing about this incident during the week and at their next press conference.

José Mourinho made the start decision to replace Matić with Ramires minutes later to increase their chances of finishing the game with 11 men.

5. Cesc Fàbregas fading

Chelsea’s Spanish playmaker had a very sloppy first half in conceding possession on a number of occasions and creating nothing for the Chelsea forwards. He’s barely had a good game since returning from injury last month.

Statistically, Fàbregas’ numbers always drop off after the first half of the season – he’s on course to continue that trend this season.