Jose Mourinho finished with five forwards on the Amex Stadium pitch last but not one of them could fill the scoring boots of Harry Kane.
Gareth Bale started only his second league match this season in a revamped front three along with Son Heung-Min and Steven Bergwijn.
But the Welshman continued to give an unrecognisable impersonation of the superstar from his first spell a the club and was hooked after 62 minutes.
Carlos Vinicius, Lucas Moura and Erik Lamela were all thrown on but could no-one could replace talisman Kane’s finishing or under-rated creativity.
The England skipper has 11 assists this seeason – the most in the Premier League – and his ability to drop deep and pick out Son Heung-Min was sorely missed.
Classy Alexis MacAllister ran the midfield and set up Leandro Trossard’s first half winer. Son, who had scored in each of his last three Premier League appearances without Kane in the team, had no-one on his wavelength.
For Tottenham’s sake, Kane needs to get well soon from his ankle injury.
Brighton’s position suddenly looks a lot healthier after ending a run of 14 Premier League home games without a win stretching back to beating Arsenal in June.
The pressure had been on with relegation rivals Fulham, West Brom and Newcastle all picking up points this weekend. But they responded in style and outplayed another North London club to move seven points clear of the drop zone.
Pascal Gross hit the post in just the third minute after neat work from MacAllister but
sloppy Spurs, who suffered only their second away defeat of the season, did not heed the warning.
The Argentine slid in Gross down the inside-right channel and the German’ss low ball was swept home by Leandro Trossard for his goal since the opening day of the season. It was too easy. And Tottenham were equally inept going forward in a dreadful first half.
Their only shot of the opening period was wide by Steven Bergwijn after 30 minutes. And Bale’s biggest contribution was blocking a goalbound Lewis Dunk header from a corner.
Mourinho sent on Carlos Vinicus for Davidson Sanchez at the break and reverted to a flat back four. At least the Brazilian looked like scoring as he forced two saves from Brighton keeper Robert Sanchez. But Brighton remained the bigger threat.
Hugo Lloris dislocated his elbow at the Amex Stadium in a 3-0 defeat and he suffered another uncomfortable mach on on 350th Spurs appearance back on the South Coast.
The France keeper saved well from a deflected Ben White shot but needed Toby Alderweireld to make a ridiculous goal-line block to deny sub Aaron Connolly a deserved second.
Tottenham have assumed the worrying habit of following long, unbeaten runs with shocking displays. Or this time two after the Liverpool defeat.
The Europa League shambles at Royal Antwerp in October followed a 10-match streak without defeat. And the midweek defeat to Liverpool ended an eight-match unbeaten run in all competitions.
Top of the table at the start of December, Mourinho’s side failed to overtake West Ham last night and remain sixth. That is now only three wins in 11 Premier League matches – and that is not all down to the absence of Kane.
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