Swansea City 2-2 Chelsea

Diego Costa has scored more goals - seven - against Swansea than against any other side in the Premier League

Chelsea dropped their first points of the Premier League season as Diego Costa struck twice to rescue a draw in a feisty encounter at Swansea City.

Costa, who might earlier have been sent off, capitalised on poor defending to fire the dominant visitors in front.

But Gylfi Sigurdsson's penalty and Leroy Fer's bundled goal two minutes later turned the game on its head.

Costa scored an acrobatic late second to salvage a point for Antonio Conte's team, who stay second in the table.

• Analysis: 'Chelsea right to feel robbed by referee'

Italian Conte was aiming to become the fourth Chelsea manager to win his first four Premier League games in charge, joining Jose Mourinho, Guus Hiddink and Carlo Ancelotti.

The visitors enjoyed total control for almost an hour before imploding with the concession of two goals in three second-half minutes. The second came after defender Gary Cahill lost the ball after he was dispossessed by Fer near the edge of his own box - with the England international saying afterwards he thought he had been fouled.

But Costa's brace at least protects the Italian's unbeaten record, with Chelsea - who ended the game with their captain John Terry appearing to be injured - now two points behind leaders Manchester City.

• Relive the action from the Liberty Stadium

• Hartson: Costa should have gone

Confrontational Costa

Having limped to 10th place last season, Chelsea had started this campaign with a swagger befitting genuine title contenders.

Costa had embodied that turnaround with two goals in his first three league games, and he was at his snarling best at the Liberty Stadium.

The Spain striker clashed with Swansea's defenders on several occasions and was booked for a clumsy challenge on Federico Fernandez, whose mistake Costa ruthlessly punished for the opening goal.

The Argentine defender hesitantly headed the ball to Oscar, whose pass allowed Costa to score with a clinical low finish.

Costa could have been dismissed against West Ham on the opening weekend before going on to net the winner - and he lived on the edge again against the Swans.

It was a small wonder he and Jordi Amat both stayed on the pitch having bickered throughout the game, and Costa was perhaps fortunate to escape a second yellow card for what appeared to be a dive under pressure from Swansea goalkeeper Lukasz Fabianski in the second half.

But as he usually does, Costa relished the confrontation and he proved Chelsea's saviour as he equalised with a bicycle kick after 81 minutes.

Diego Costa's touchmap shows that he prowled all over the Swansea half - his play is not limited to the opposing area

Swansea's controversial revival

Having lost their previous two fixtures, the Swans were staring at the prospect of suffering three successive defeats under Francesco Guidolin for the first time.

In what appeared to be an attempt at damage limitation, the Italian switched to a defensive 5-4-1 formation with a compact midfield diamond aimed at containing Chelsea.

Those efforts were in vain as the Swans were initially overrun and outclassed by their rampant opponents.

Guidolin abandoned his new system after just 41 minutes, with Wales left-back Neil Taylor dismayed as he was sacrificed for winger Modou Barrow.

The bold move paid dividends as Swansea staged a remarkable second-half revival.

They were awarded a penalty when Sigurdsson was tripped by a stranded Thibaout Courtois, who was the beneficiary of a rule change which means players are only booked rather than sent off if they are deemed to have only accidentally denied their opponent a goalscoring opportunity.

Sigurdsson confidently converted the spot-kick, and the fans had barely had time to catch their breath before the next controversy.

Fer appeared to foul Cahill as he dispossessed the Chelsea defender, and Swansea's Netherlands midfielder ran clear before squeezing his shot past Courtois and over the line.

Man of the match - Diego Costa

Costa was as aggressive in his all-round play as he was clinical in front of goal - the Spain striker was a constant menace for Swansea's defence

'It's a big mistake' - what the managers said

Chelsea boss Antonio Conte: "It's very difficult to talk about the game because we lost two points. We were leading 1-0 and created a lot of chances to score another goal. We are disappointed because the performance was very good in terms of our intensity and because we played good football.

"People looking at the second goal can see that the referee made a mistake - but this can happen. I've not spoken to the referee. It's a big mistake."

Swansea boss Francesco Guidolin: "I am happy with the result. My team played the second half with more energy against a very strong team.

"After Chelsea's first goal I saw my team not playing well and decided to change something before the end of the first half. I am sorry for Neil Taylor [getting substituted] but I decided this way because we needed a reaction."

The stats you need to know

• Only five players have reached 35 goals in the Premier League in fewer appearances than Costa (58) - Andy Cole (41), Alan Shearer (42), Fernando Torres (52), Kevin Phillips (52) & Ruud van Nistelrooy (55).

• Costa's opening goal was also the 100th scored in the 2016-17 Premier League season.

• There were just two minutes and 10 seconds between Swansea equalising and scoring their second goal.

• Sigurdsson has now scored more Premier League goals for Swansea than any other player (26).

• Eleven of the 13 outfield players to play in this match for Chelsea attempted at least one shot.

What next?

Chelsea's burgeoning title credentials will be tested by their next two games, at home to Liverpool and away against Arsenal.

Swansea, meanwhile, face a daunting sequence of fixtures - a trip to Southampton followed by home matches against Manchester City and Liverpool and then a visit to Arsenal.