Tottenham's hopes of returning to the Champions League are far from vanquished but, after a 1-0 home defeat to top-four rivals Leicester City, they are in peril.
Victory would have kept them in touch with the top three. Instead, their defeat has opened a four-point gap to third-placed Manchester City.
For now, instead of looking up the table, Spurs must look over their shoulder at the logjam of teams behind them.
Spurs needed to find a way to win this game.
A tight 1-0 defeat at home to the division's third-ranked team would ordinarily be no source of embarrassment.
This is not an ordinary season, and Leicester's place at the top of the table is proof of that.
In Sunday's FA Cup draw between these two, Spurs were unable to make rapid transitions when they won the ball.
That failure to quickly turn possession won into an attack translated into a stalemate for long periods. Leicester were unwilling to deviate from their game plan, and Spurs were left playing endless passes in front of the massed ranks of defenders.
It may be a trite observation to say that taking chances is key to winning a football match, but against Leicester it is especially true.
The Foxes play only one way.
It is a very deliberate, predictable approach that concedes a majority of the possession and field position to their opponent before attempting to score on the counter-attack.
That tactic is designed to sap the physical and mental energy of their opposition–to frustrate them and encourage them to push players forward and make dangerous passes in order to break them down.
This match was always likely to play out the way it did and should certainly have come as no surprise to Spurs manager Mauricio Pochettino in their fifth meeting with Leicester in less than a year.
They made 21 attempts on Kasper Schmeichel's goal but had only a handful of good chances.
Tom Carroll and Christian Eriksen dovetailed nicely, buzzing around Leicester's defensive wall searching for an opportunity.
Erik Lamela had an excellent game, Harry Kane was worked tirelessly and Dele Alli gave a driven, mature performance.
Between Sunday's FA Cup draw and Wednesday's defeat, Christian Eriksen told Spurs' official website that the team needed to take their chances.
"We did alright on Sunday, we didn’t let them have any really big chances and we need to do the same, but be a bit sharper when we get the ball in the final third."
Unfortunately, they failed to heed his advice.
Had Tottenham won this game, it would have been hailed as reflective of their progress.
The best teams find a way through.
In Arsenal's 5-2 win over Leicester in September, they had a 2-1 half-time lead and were able to pick three more goals as the Foxes searched for a way back into the match.
It would be an oversimplification to say that Pochettino's system has been figured out, but a recurring theme of failing to convert dominance into goals and wins is a concern.
This is poised to be a historically low season in terms of points accrued.
Seventy-two, or thereabouts, has traditionally been the threshold for fourth place and Champions League football.
This season it is almost certain to be around 10 points fewer.
That means that wins carry more weight than usual, and this counts doubly for games between contenders.
The four-point gap between Spurs and the teams above them is daunting.
Overcoming the disadvantage that Tottenham have given themselves will be the defining narrative of the coming weeks and months.
After Spurs' last defeat, they won three on the bounce and solidified their top-four place.
A similar response is desperately needed now.