If José Mourinho had hoped to discover a workable plan B in Harry Kane’s absence, this wretched offering from Tottenham confirmed a return to the drawing board will be necessary. They were outplayed from the first minute to the very last by Brighton, who were excellent to a man, and such a bland showing bodes ill for the coming weeks. The sight of Gareth Bale walking off in the 61st minute after a near-anonymous performance was a reminder they have more than one problem in attack, although that was far from the only department in which they struggled against opponents whose superiority was often startling. Brighton had not won any of their previous 14 home games but would not have been flattered by the 3-0 margin they amassed here during the dying throes of Mauricio Pochettino’s reign. Their winning goal was of a piece with the smart, incisive football they produced throughout. When Alexis Mac Allister slipped Pascal Gross through on the right of the area the situation demanded a clever cutback. It duly received one, Gross finding Leandro Trossard for a clipped, first-time finish that gave Hugo Lloris no chance. Trossard had not scored since September; it was quite a time for him and Brighton, who had lacked cutting edge ever since, to discover their killer touch. That was in the 17th minute and Brighton could already have been a goal up by then, Gross hitting the post with the outside of his foot after a lovely move involving Mac Allister and Neal Maupay. They were dominant in the opening period and Mac Allister, who is quietly becoming a highly impressive operator, was their standout performer. He dipped a shot off target, saw another deflected wide and probed intelligently in the yawning chasms between Spurs’ defence and midfield. Tottenham never looked like getting a foothold and Mourinho was left to regret what he called a “lack of confidence, lack of self-esteem” in his players before half-time. “In the first half I felt the team was probably too sad with the goal conceded and the situation,” he said. “There was a lack of energy.” That was true but Mourinho’s analysis of the second half was, putting it kindly, far more generous. He felt Spurs had showed “great spirit” but it was hard to detect much change. After an error-strewn 45 minutes against Liverpool in midweek he had hauled off Serge Aurier, who subsequently left the stadium and did not even make the bench here. That, Mourinho said, was a “technical decision”. This time he relieved Davinson Sánchez of his duties at the interval, putting Carlos Vinícius up front in an attempt to make attacks stick, but the improvement was minimal. Vinícius planted an angled header against Robert Sánchez’s legs soon after coming on and, with 15 minutes left, drew a superb save from the keeper with a shot on the turn. That was about it: Spurs, for whom Son Heung-min was peripheral and Steven Bergwijn more or less invisible bar a first-half shot he dragged wide, never managed to mount a sustained threat. That is where Bale’s name comes back in, given he needed to make an impression on only his second top-flight start since returning. Kane is likely to miss their next five games even if analysis of his ankle injury returns a best-case scenario and Mourinho can ill-afford to spend that time handling his expensive loanee with kid gloves. Bale started on the right but had been shifted across by the quarter-hour. It was not that he did much wrong: he might even have written a very different story if Son had not botched a chance to play him through early on, and he produced a solid piece of defensive work in clearing a Lewis Dunk header from near the line. But the old speed, strength and incision were not there and it would appear some gamble for Mourinho to give him another bite against Chelsea on Thursday. “I’m not speaking about Bale, I’m speaking about us,” Mourinho said of Spurs’ inability to stitch fluent attacks together. They could do worse than examine how Brighton managed to do that. While Mourinho suggested his team “deserved more than what we got” after the break, simple observation told a truer story and the home substitute Aaron Connolly would have made that clearer if he had not allowed Toby Alderweireld to block late on with the goal gaping. Brighton would have felt sick if that miss had proved costly. “It’s our best performance this season and last,” Graham Potter said. “I thought it was closer to a 2-0 than a 1-0.” That was a sounder appraisal; clear daylight now shines between Potter’s team and the bottom three but, however Mourinho spins it, Spurs will spend the coming days under a cloud.