Turning their attention away from a seven-game winless run in the Premier League, Spurs came into this final league phase match knowing victory over an unfancied Elfsborg would guarantee a spot in the top eight.
Unsurprisingly, Tottenham were on top from the off, yet they struggled to create clear chances as Ben Davies headed over from a corner.
Captain Son Heung-Min was causing the visiting defence issues down the left, and he manufactured the two best opportunities of the half, the first of which came after skipping past Besfort Zeneli and finding Pape Matar Sarr with a deflected pass.
The Senegal international saw his goal-bound shot cleared before Mikey Moore was denied by Isak Pettersson’s reaction save, having also been teed up by Son.
Coming into this clash, no UEL side had seen less of the ball than Elfsborg, so it was perhaps unsurprising that the Swedish side looked relatively comfortable out of possession.
Having absorbed plenty of pressure, Di Gule almost snatched an unlikely lead after the break when Zeneli’s deflected shot broke to Jalal Abdullai, who produced an acrobatic effort that cleared the crossbar from close range.
Tottenham’s injury crisis has been well documented, particularly in defence, and just as Micky van de Ven made his long-awaited return with 45 minutes of action, his replacement Radu Drăgușin was forced off injured.
Thankfully for the home support, they soon had something to celebrate when HT substitute Dejan Kulusevski’s wonderful delivery found returning loanee Dane Scarlett, who darted into the box and headed home his first goal for Tottenham.
Thanks to results elsewhere, Elfsborg were in danger of missing out on the play-offs, and their GD was dealt another blow as Spurs doubled their lead late on through debutant Damola Ajayi, who combined well with Scarlett before stroking a neat shot into the corner.
Moore rounded off the scoring with his first Spurs goal deep into stoppage time after a solo run, sealing an 11th consecutive unbeaten UEL match at the Tottenham Hotspur Stadium (W9, D2) that sees Ange Postecoglou’s side through to the last 16 with a fourth-place finish in the league phase standings.
Only a win would have guaranteed Elfsborg passage to the play-off round, and devastatingly for them, an inferior GD saw the Swedish side miss out by the most slender of margins.