Alyssa Thompson’s first-half strike secured victory for Chelsea in a fierce London derby, as Arsenal’s unbeaten start to the season came to an end.Katie McCabe was booed throughout the game in an attritional first meeting between the former Arsenal star and her new side.Ultimately McCabe and her new team-mates had the last laugh, however, with the likes of Lexi Potter and Keira Walsh also starring in midfield in a dominant display for the hosts.Daily Mail Sport’s women’s football reporter TARA ANSON-WALSH was at Stamford Bridge to give you the things we learned… Alyssa Thompson’s first-half strike secured victory for Chelsea in a fierce London derbyAre Arsenal out of the title race already?Much has been said about Arsenal’s lack of goals this season, but the more worrying thing from a fan’s perspective has been the lack of urgency in their play.Renee Slegers’ side dominated Chelsea for possession and chances in the opening stages of this game, with Kim Little and Mariona Caldentey both hitting the woodwork. But the stats relating to their domination for chances miss the fact that they simply appear off it. Tired, slow, frustrated, lacking confidence.Nine times out of ten Caldentey would have buried that first-half chance when she broke free and went one-on-one with Hannah Hampton. Alessia Russo meanwhile hasn’t found the back of the net yet this season. It appears Russo has fallen victim to Slegers’ lack of conviction over who should be the starting No 9 between her and Stina Blackstenius, and she hasn’t been allowed to build momentum in either role.Where the goals are going to come from remains unclear at this stage, as is the injection of conviction that is clearly needed in their press, which appears to have fallen off a cliff.The passage of play leading up to Chelsea’s winner, where Arsenal were caught off guard playing out from the back and passed up the chance to mop up, summed this up. Ellie Carpenter and Melvine Malard gave the Gunners a lesson in tenacity.It wasn’t until Chloe Kelly and Caitlin Foord were introduced in the second half that a sense of life was breathed into the Arsenal attack. But by then, it was too late.The Chelsea players collapsed to the floor at the final whistle, and Sonia Bompastor thumped the air. They looked like they merely wanted it more.Arsenal are now seventh in the top flight, seven points behind league leaders Manchester City. Historically, the WSL has been decided by notoriously fine margins.Should Arsenal beat City next weekend, their title race could still be salvaged. But currently that appears to be hanging by the most fragile of threads. It appears Russo has fallen victim to Slegers’ lack of conviction over who should be the starting No 9 between her and Stina Blackstenius, and she hasn’t been allowed to build momentumShould there be questions over Slegers?This all brings us to the question: does Renee Slegers still have what it takes to lead this team forward?When the 37-year-old was appointed head coach of Arsenal in October 2024, it felt like the squad needed a mental reset. Someone to figuratively wrap an arm around the players after a tense close to Jonas Eidevall’s tenure.The bounce from Slegers’ injection of positivity and clarity – full back Emily Fox described her as a ‘steadying force’ at the time – was so influential that it carried the Gunners to the Champions League final, which they won.To say that the fairytale of Lisbon was a one-off for Slegers is harsh, but there are warning signs that her side lack the ruthlessness needed to end their seven-year wait for a league title.Arsenal had a slow start to the season last campaign, and were eight points behind City by Christmas. Although they only lost the one game all season against the eventual champions, two early draws ultimately proved costly as they fell away early. Likewise, they have dropped seven points this season.To add to that, Slegers has a sizeable squad full of international starters. Having the likes of Chloe Kelly, Olivia Smith and Caitlin Foord on the bench speaks to a position of privilege, but it appears Slegers is grappling this season with big names, form and how those factors interact. With a World Cup less than a year away, her ability to manage this squad going forward could prove a sticking point.While it’s certainly too early to call for any decisive changes to be made, the pressure is certainly ramping up. While it’s certainly too early to call for any decisive changes to be made, the pressure is ramping up on Renee SlegersChelsea finally show their teethThere were multiple questions asked throughout last season about whether Chelsea had lost their winning mentality, with Sonia Bompastor’s side often lacking the ruthless edge to push these tight contests over the line.In a match which saw clear swings in momentum and tested their defensive resilience, Bompastor’s side stood tall.‘The plan for us this season is in terms of mindset and mentality, and I think I’ve been talking a lot about that, to be strong and to be together,’ Bompastor said.‘I think no matter what happened in the game, I always want to see a group of players, but also a team who is together in our high moments when we are doing well, but also in the low moments.‘I think we came into this game well prepared in terms of we knew we were going to have some moments in the game where we were probably not in control, especially in possession of the ball.‘So we prepared the game for those moments to be still moments where we were in control, even if we didn’t have the ball, we knew exactly where we wanted to orientate the ball, where we wanted to leave some spaces, and I think we dealt with that really well.‘We were also really strong in terms of not only mental but also physical aspects. Winning the duels, defending the box, and not conceding against a team with strong attacking talent.’It’s still early days, but Bompastor’s side showed their bite at Stamford Bridge in a way that was clearly lacking last term, and one that could prove useful for them as they look to reclaim their crown. They certainly look up to the task. It’s still early days, but Bompastor’s side showed their bite at Stamford Bridge in a way that was clearly lacking last term – while Katie McCabe shone against her former sideA bit of needle is good for the gameThe departure of Jonas Eidevall and Emma Hayes were supposed to signal the end of the WSL’s fiercest rivalry, but luckily for the neutral, this fixture hasn’t stopped giving.Katie McCabe’s transition from red to blue this summer has helped that in no small part. She was given a sign of things to come when she received a chorus of boos while kneeling down to take the team photograph.The boos followed her every touch throughout the game, while Chelsea fans responded by singing her song with gusto.As it turned out McCabe had an excellent game, with Sonia Bompastor commending her attitude after the full-time whistle.‘That’s never easy for a player, who has been there for so many years, to face that club,’ she said. ‘Katie is one of those characters where people boo, that gives her more motivation. I think they probably should have kept quiet.’More of these, please.