Harry Kane scored on his return to the Tottenham side but their Premier League title hopes were dented by a 2-1 defeat to Burnley at Turf Moor.
Kane came straight back into the starting line-up after seven games out with an ankle injury and produced a smart finish to equalise in the 65th minute, eight minutes after Chris Wood had given the hosts the lead.
Victory would have moved Spurs to within two points of Manchester City and Liverpool at the top of the table but Burnley showed why they have not been beaten in the league since Boxing Day.
They had come close to a second before substitute Johann Berg Gudmundsson set up Ashley Barnes for an 83rd-minute winner.
Sean Dyche had speculated that Spurs may choose not to risk Kane with games against Chelsea and Arsenal to come over the next week but Mauricio Pochettino billed this contest as like a final for their Premier League chances.
Since the nadir of a 5-1 home loss to Everton, Burnley have tightened up at the back, shown an increased goal threat and an all-round improvement in organisation, intensity and sharpness.
They showed that from the start, with Barnes and Wood - who had scored six goals between them in the previous three games - proving a handful for the Spurs defence.
Kane unsurprisingly looked a little rusty, taking a couple of heavy touches, but he produced the first real effort on goal in the 16th minute when he drove towards the edge of the box and shot just wide.
At the other end, Barnes came as close as anyone to a goal in a low-key first half with a well-struck shot that curled just over the bar, while Kane was warming to his task and, after Tom Heaton was off his line smartly to pounce at the striker's feet, Kane headed straight at the keeper.
Both men dialled it up several notches in the 50th minute as Kane set his sights on the top corner and let fly with a superb, swerving shot that looked poised to find its target until Heaton flung out a hand and tipped it behind.
Burnley were struggling to get out of their own half but a smart turn by Dwight McNeil under pressure in midfield led to the hosts taking a shock lead.
His pass set Charlie Taylor away down the left and the full-back's cross was eventually scrambled behind for a corner. McNeil stepped up to take it and delivered the ball onto the head of Wood, whose effort hit the underside of the bar and bounced down over the line.
Pochettino, who appeared furious at the award of the corner, responded by bringing on Fernando Llorente in place of Harry Winks but it was that man Kane who provided the equaliser.
A quick throw from Danny Rose caught out the Burnley defence and Kane got in behind, drove into the box and poked the ball confidently past Heaton.
It was a more open game now and, after Juan Foyth was booked for a late challenge on Wood, a nice move ended with Jeff Hendrick shooting just wide, while McNeil was denied by Hugo Lloris as Spurs were caught short at the back.
They did not heed the lesson, though, and, moments after coming on, Gudmundsson drove into the box and his cross-cum-shot was tucked away at the far post by Barnes.
Spurs pushed for an equaliser in four minutes of injury time but Erik Lamela's header, gratefully grasped by Heaton, was as close as they came.
Pochettino was involved in a lengthy exchange with Dean in the centre circle after the final whistle before finally heading off down the tunnel.