All evening, Thomas Tuchel gave off the energy of a man who was waiting for something to go wrong. He flung his arms in the air, he stood with his hands on his head and at times he simply muttered to himself, his irritation clear as he watched Chelsea’s players take it in turns to offer the initiative to Brighton. There was no way of fooling Tuchel, even when Hakim Ziyech gave Chelsea a hugely undeserved lead midway through the first half. The German knew better than to expect Brighton to lie down. Potter’s side were the stronger throughout and Chelsea, who are winless in their last four league matches, could have no complaints when Adam Webster cancelled out Ziyech’s goal midway through the first half. The European champions, who have more chance of getting dragged into a top-four battle than of cutting Manchester City’s lead at the top, did not look like a happy side. Tuchel’s negative body language seemed to have a sapping effect on his players. Even Mason Mount looked like he had the weight of the world on his shoulders and nothing was more revealing than Romelu Lukaku, who was taken off with 10 minutes left, squabbling with Ziyech as the teams walked off at half-time. Little went right for Chelsea before the interval. Indeed, Tuchel barely offered any celebration when Ziyech scored. Too passive when they lost to Manchester City on Saturday, Chelsea had not convinced before going ahead. Their passing was sloppy, the error count was high and Brighton were the sharper side from the start. Brilliantly drilled by Graham Potter, Brighton dominated the early stages. Steven Alzate and Pascal Gross set a brisk tempo in midfield for the home side and Chelsea struggled with Brighton’s frenetic pressing, César Azpilicueta, Jorginho and Ziyech all giving the ball away in dangerous areas. The problem for Potter’s team, though, was a familiar one. Jakub Moder skewed wide from the edge of the area after combining with Danny Welbeck, who would also bungle an opportunity, and it did not come as much of a surprise when Brighton’s lack of bite proved costly. Chelsea, who used a 4-2-2-2 system, had started to exert a modicum of control before Ziyech’s goal. There was a warning for Brighton when Lukaku briefly flickered, loping down the right before presenting Azpilicueta with a chance to test Robert Sánchez. For all their lethargy, Chelsea still had players who could conjure something out of nothing. Ziyech, surprisingly selected after disappointing against City, was a case in point. The winger was a one-paced irrelevance for long spells, but at least he made a positive contribution in the 28th minute, taking a pass from N’Golo Kanté before cutting in from the right and catching Sánchez out with a low drive from 25 yards. Sitting on the bench by that stage, Tuchel still looked unimpressed. No doubt he had a few choice words to say when Callum Hudson-Odoi, who lacked an end product after being asked to partner Lukaku, fired over when he should have doubled Chelsea’s lead. Chelsea remained vulnerable. Brighton should have equalised at the start of the second half, only for Welbeck to miss with an angled drive. Welbeck’s pace was worrying Antonio Rüdiger and Thiago Silva, but the Brighton striker was not alone in causing havoc. Tariq Lamptey kept sprinting at Marcos Alonso, whose booking for fouling the right-back was utterly predictable, and Kanté and Jorginho had become increasingly swamped in the middle, the clever interchanges between Marc Cucurella, Alexis Mac Allister and Moder leaving Chelsea dazed and confused. With Lukaku unable to shake off Webster and Dan Burn at the other end, an equaliser seemed inevitable. Mac Allister went close, Kepa Arrizabalaga pushing the Argentinian’s deflected shot away for a corner, but the pressure was growing. The cross came in from Mac Allister and Webster, completely unmarked, crashed a header past Arrizabalaga. Level at last, Brighton threw on Neal Maupay and Leandro Trossard. They poured forward, though they were lucky to escape when Rüdiger released Lukaku and Sánchez turned the striker’s shot wide. Tuchel responded, taking Lukaku, Jorginho and Ziyech off for Timo Werner, Kai Havertz and Mateo Kovacic, but there was no late show from Chelsea. It would have been undeserved.