Chelsea fans found themselves on an extended trek to Stamford Bridge over the weekend, thanks to the District Line suspension at Fulham Broadway. Despite the inconvenience, there was plenty for them to chat about as they made their way to the nearest tube station.

The main topic of conversation was likely Chelsea’s inconsistency. Each time the team seems poised to join the title race, they reveal why they haven’t quite reached that level yet. Enzo Maresca’s youthful squad has dropped more points from winning positions than any other team this season, missing a prime opportunity to climb to second place in the Premier League.

While reflecting on their own team’s lapses, Chelsea supporters might have also spared a thought for the impressive rise of Sunderland.

Sunderland’s stellar start to the Premier League season is the best since Hull City’s in 2008-09. Their unexpected success is causing anxiety among rivals like West Ham, who now fear that they might be the ones facing relegation instead.

Sunderland’s astute manager, Regis Le Bris, maintains a grounded approach, emphasizing that their goal remains reaching 40 points. “We haven’t even reached halfway to that goal yet,” he remarked. “We still need three more points.”

Chelsea struggled to present any sort of creative attacking threat as they lost late on at home

Sunderland are very munch the surprise package of the start of the season and sit second

Given Sunderland’s ability to challenge their opponents, they are likely to achieve their target sooner rather than later. They have not entered the Premier League with an overconfident attitude, recognizing that on paper, some teams might still be stronger than they are.

But they play with a smart philosophy, with a team spirit, and with an edge which will give any side a run for their money, as Chelsea, who have thrown plenty of cash in their pursuit of success, discovered here in defeat.

They do the basics and do them well. Sunderland defended deep in a 5-5-0 formation without the ball. But they still showed quality with their players flying forward once they had won possession. They tried to force Chelsea into pushing their play wide as they made the central areas as congested as possible.

Led by an experienced captain in Granit Xhaka, they were dedicated to that cause, so much so that they forced Chelsea into the most crosses they have produced in any Premier League game this campaign. That smacked of a side out of ideas in attack. Indeed this was one of those matches where Maresca clearly missed Cole Palmer’s ingenuity as those filling in resembled only robots programmed to go from side to side.

Alejandro Garnacho scored early on, but then hardly created any chances of note from then on. When substituted after 76 minutes, Garnacho wore a grumpy look, walking slowly as Maresca urged him to get a move on. Jamie Gittens came on in his place but did not follow up on the positive performances he had shown in previous weeks. Pedro Neto was similarly subdued. Joao Pedro’s contribution was minimal.

Marc Guiu spent 26 days on loan with Sunderland at the start of this season before being recalled by Chelsea. We wondered if he would celebrate if he scored. He never came close to answering that question, limited to 10 touches all game by his opponents. Tyrique George was given five minutes to try to have an impact as a striker but could not.

Again, we should give Sunderland the credit for silencing Chelsea so.

Regis Le Bris has been keen to play down aspirations beyond their main goal of staying up

Alejandro Garnacho opened his Chelsea account but did not trouble Sunderland thereafter

Enzo Maresca was disappointed at full-time with both his attackers and defenders on Saturday

Marc Guiu was only able to make 10 touches on the heels of a threatening European outing

Sunderland snatched victory at the last courtesy of a great counter-attacking strike from Chemsdine Talbi

Captain Granit Xhaka has proved an astute piece of recruiting for Le Bris’ well-unified side

The Blues ought to have used Garnacho’s opener to kick on, but instead, they allowed Sunderland back into the game via a simple long throw-in. Maresca had shown his players clips of the goal they conceded at Brentford in the build-up to this clash. He knew long throws were a possibility here because his analysts told him so. Then Sunderland scored from their first such opportunity. When new to the Premier League, it is important to seize your chances, and there is nothing wrong with a long launch.

As well as the toothlessness of Chelsea’s attack, Maresca made mistakes which Le Bris capitalised upon. Chelsea’s head coach waited late to make substitutions and one of them in the 76th minute was to remove one defender for another – Josh Acheampong for Tosin Adarabioyo. Only he knows why.

Acheampong had been the centre back stopping Sunderland’s counter-attacks up until then. In stoppage time, Lutsharel Geertruida launched the ball long from his own half. Brian Brobbey held it up, outmuscled Adarabioyo, and waited for Chemsdine Talbi to join him.

Le Bris brought on Brobbey because of his ability to hold up the ball, and Talbi for his energy. Then those two substitutes combined for the winner. Any Chelsea claims that Geertruida might have been interfering from an offside position were in vain.

Maresca’s day was summed up best with the last kick of the game. They had a corner; a chance to equalise from a set-piece. Estevao took it, but sent the ball straight into the side-netting. Not even their Brazilian boy wonder was on his game this time.

Speaking afterwards on Sunderland’s dream start to life in the Premier League, Le Bris said: ‘What we can control is our way of playing, the energy we put on the pitch, the togetherness, the game plan. We fight for every game.’

Indeed, Sunderland are not here to go back down with a whimper like others in their position have done. They are admirably and unapologetically shaking up the Premier League for the better.