Tottenham's Champions League campaign is up and running after Son Heung-Min scored his fifth goal in as many games to snatch a 1-0 win over CSKA Moscow.
Spurs dominated possession in the newly-built CSKA Arena but struggled to break down their resilient opponents until Son struck in the 71st minute to seal an invaluable three points.
The victory lifts Mauricio Pochettino's men up to second in Group E and only a point behind leaders Monaco, who drew 1-1 at home to Bayer Leverkusen.
Much of the talk in the build-up to this contest surrounded Harry Kane's return from injury but Son has now scored three goals in the two matches since Kane was carried off on a stretcher and this was arguably his most important.
Tottenham sat bottom of the standings at kick-off following their disappointing opening defeat at home to Monaco and this result puts them back in the hunt for top spot, in a group that looks unlikely to produce a runaway victor.
Pochettino had little room to manoeuvre in his starting lineup given Kane, Danny Rose, Eric Dier, Mousa Dembele and Moussa Sissoko were all left at home to recover from injury, but there was one surprise as Kieran Trippier began ahead of Kyle Walker at right-back.
Dele Alli dropped into central midfield despite lasting only 45 minutes there against Monaco at Wembley, but in possession the 20-year-old spent most of his time behind Vincent Janssen, Pochettino deploying an ambitious formation of 4-1-4-1.
It meant Spurs were never short of bodies in the final third but they were also vulnerable to the counter-attack, where CSKA looked dangerous, particularly in the opening stages.
The hosts had an early claim for a penalty when they thought Jan Vertonghen blocked Zoran Tosic's shot with his arm but the referee awarded nothing more than a corner.
Spurs began to settle after 15 minutes but were almost punished when Alli over-ran the ball in midfield, with Lacina Traore's driving run only stopped by a last-ditch challenge from Toby Alderweireld.
Eriksen unleashed a shot from long range, the visitors' first attempt in the 23rd minute, but when CSKA defended they did so in numbers and Tottenham struggled to find a way through.
Alli went closest shortly after the half-hour when his shot from 25 yards clipped the top of the crossbar before Alderweireld had a free header, picked out by Trippier's ball over the top, but could only find the grateful hands of Igor Akinfeev.
Both sides had chances at the start of the second period as first Son was sent clear by Victor Wanyama but took too long to shoot and then at the other end Traore's cut-back found Tosic, but his finish was deflected over.
Tottenham were dominating possession but chances remained few and far between, with Pochettino opting to replace his striker Janssen in the 66th minute with the more pacey and unpredictable Georges-Kevin Nkoudou.
It worked, as five minutes later they took the lead, Lamela driving through midfield and setting free Son, whose poked finish sent the ball under Akinfeev and dribbling over the line.
The goal forced CSKA to push forward in search of an equaliser and they went close when Roman Eremenko tested Hugo Lloris from distance before Mario Fernandes flashed a ball across the face of goal. Spurs, however, were not to be denied, holding on for what could prove a crucial victory.