London - Tottenham need another Champions League escape act to reach the quarter-finals after Timo Werner's penalty earned RB Leipzig a deserved 1-0 last 16, first leg win in London.
Spurs captain Hugo Lloris kept his side in the tie with a string of important saves, but last season's finalists face a huge task to turn the tie around in Germany on March 10.
Without the firepower of the injured Harry Kane and Son Heung-min, Giovani lo Celso's free-kick that struck the post was the closest Jose Mourinho's men came to scoring on the night.
Tottenham upset the odds to progress past Manchester City and Ajax in the knockout stages last season, but were lacking in ideas and energy compared to the Bundesliga contenders.
After receiving the news that Son could be sidelined for the rest of the season by a fractured right arm on the eve of the game, Mourinho compared his side's prospects for the rest of the season to hanging from a fourth-floor building by the balcony.
The hosts could easily have fallen flat on their face inside the first 90 seconds as Leipzig amazingly passed up four chances to open the scoring.
Patrik Schick flashed a shot wide from the edge of the box before Werner's effort was blocked and Lloris turned Angelino's driven shot onto the post.
Lloris then had to be alert again to deny Werner adding to his 25 goals this season from close range.
After weathering that early storm, Spurs went close to at the other end through Steven Bergwijn.
The Dutch international has enjoyed an impressive start to his Tottenham career and forced Peter Gulacsi into a smart save low to his left.
Leipzig are challenging Bayern Munich's grip on the German title this season and the visitors were not overawed by the stage in their first ever Champions League knockout tie.
Lloris was forced into another save by Schick before the towering Czech also headed just wide from a corner.
Werner then wasted the best chance of the first half when he fired too close to Lloris with just the French number one to beat.
Leipzig could have regretted not making the most of their supremacy during the first 45 minutes as Gulacsi saved well from Lucas Moura and Bergwijn fired the rebound wide early in the second period.
However, after grinding out wins over Manchester City, Norwich, Southampton and Aston Villa in recent weeks despite conceding plenty of chances, Spurs' luck ran out.
An ill-timed lunge from Ben Davies chopped down Konrad Laimer inside the area and Werner confidently converted the resulting penalty.
Moments later only a fine save by Lloris denied Schick a second at the end of a flowing move involving Christopher Nkunku, Angelino and a delightful dummy from Werner to tee up his strike partner.
The introduction of Erik Lamela and club record signing Tanguy Ndombele from the bench gave Tottenham a much-needed injection of creativity for the final 25 minutes.
However, their best effort came from a set-piece when Lo Celso's powerful free-kick was turned onto the post by Gulacsi.
Lucas then headed over a great chance two minutes from time as Spurs peppered the Leipzig box with crosses, but Julian Nagelsmann's men held out for a landmark win.