Chelsea are still searching for a winning formula after they were held to a 1-1 draw at London rivals West Ham.
The Blues, boosted by a £300million spending spree last month, took the lead through one of their seven January buys, Joao Felix.
But West Ham equalised thanks to Chelsea old boy Emerson Palmieri and, once again, Graham Potter’s expensively-assembled side were unable to find a winner.
It is now just one win in seven since the turn of the year for Chelsea, while Potter’s record reads five wins, six draws and five defeats from his 16 Premier League games in charge.
Injuries meant West Ham could not fill their bench, with David Moyes naming just eight subs including two rookie goalkeepers.
Potter, by contrast, was able to welcome back Felix from suspension after his promising debut against Fulham was ended prematurely by a red card.
The Portuguese winger carried on where he had left off at Craven Cottage, and had already had one goal ruled out for offside when he put Chelsea ahead in the 16th minute.
Marc Cucurella advanced down the left before playing the ball back to £106million man Enzo Fernandez, another of the five January recruits in the Blues starting line-up.
The Argentinian World Cup winner swung in an inviting cross which Felix simply had to guide into the back of the net.
Things began to look ominous for West Ham when Mykhailo Mudryk’s slide-rule pass was converted by Kai Havertz, but once again the offside flag came to their rescue.
Yet the hosts equalised in the 28th minute when Vladimir Coufal’s cross was flicked on by Jarrod Bowen for Emerson to tuck away at the far post.
Chelsea could have snatched the lead again before half-time but Lukasz Fabianski saved from Noni Madueke and a Felix free-kick, while Benoit Badiashile headed over from a corner.
After the break Declan Rice, enjoying his midfield duel with Fernandez, managed to get forward and fizzed a shot narrowly wide.
Potter turned to the old guard with a triple substitution to introduce Hakim Ziyech, Ben Chilwell and Mason Mount.
Chilwell almost had an instant impact, denied a goalscoring opportunity by Nayef Aguerd’s superb tackle before delivering a cross which Havertz headed wide.
West Ham thought they had won it with nine minutes left after Tomas Soucek snaffled a rebound at the far post, but after a lengthy VAR review Rice, whose initial header had been saved, was ruled offside.
Soucek was then fortunate to avoid being penalised for a handball which diverted Conor Gallagher’s shot wide as Chelsea were left frustrated again.