Thomas Frank enjoyed a winning Champions League debut as a calamitous fourth-minute mistake by Villarreal goalkeeper Luiz Junior sealed a narrow victory for Tottenham.

Under no pressure, Junior fumbled Lucas Bergvall's cross into his own net to hand Spurs the dream start in front of their own fans.

This is the first time ex-Brentford boss Frank has managed in this competition but his Tottenham side lived dangerously at times before the break, with only a crucial intervention by Micky van de Ven preventing ex-Arsenal winger Nicolas Pepe from curling in, while Tajon Buchanan dragged a shot wide when he looked certain to score.

But only a good save by Junior denied Tottenham adding a second midway through the first half when he kept out Pape Matar Sarr's strike.

Villarreal came on strong in the second half but Tottenham defended superbly to repel them.

Richarlison should have done better with a header as Spurs tried to get the security of a second goal, but ultimately it was not needed.

Former Arsenal midfielder Thomas Partey came on for Villarreal in the closing stages, despite being due to appear in court on rape and sexual assault charges in London on Wednesday.

Ghana midfielder Partey, 32, was charged last month with five counts of rape against two women and a charge of sexual assault against a third woman.

It was the first match he has played in England since the allegations first came to light.