Tottenham’s return to Champions League football ended in disappointment with a 2-1 defeat to Monaco in front of a record crowd at Wembley.
With Spurs playing their Champions League games at the national stadium this season because of the development of their new stadium, 85,011 - a record home attendance for an English club in any competition - saw Monaco race into a two-goal lead.
Bernardo Silva (15) and substitute Thoma Lemar (31) got on the scoresheet for the visitors, but Spurs got back into the game just before the break with Toby Alderweireld (45) pulling a goal back.
Mauricio Pochettino turned to Mousa Dembele at the break as Spurs improved, but Harry Kane missed a glorious 79th-minute chance as the equaliser proved elusive, leaving the the large Spurs contingent at Wembley disappointed.
Monaco, who handed former Manchester United and Chelsea striker Radamel Falcao a start on his return to England, suffered an early set-back when Nabil Dirar was forced off the pitch through injury and he was replaced by Lemar.
And it was Spurs, backed by the record crowd at the national stadium, who started strongly. Kane's cross found Son Heung-min at the far post and the South Korean's shot beat goalkeeper Danijel Subasic, but it was cleared off the line by Andrea Raggi.
Spurs continued to control proceedings and they had another opportunity in the 15th minute when the ball fell to Dele Alli in the box, but the England midfielder's shot deflected into the arms of Subasic.
However, just three minutes later Wembley was left stunned after Erik Lamela gave the ball away in midfield. Silva picked up the ball and ran at the Spurs defence and with Jan Vertonghen standing off him, the midfielder produced a brilliant finish to beat the dive of Hugo Lloris.
Lamela looked to atone for his error straight away, forcing Subasic into a low save but things got even worse for Pochettino's side in the 31st minute.
Spurs failed to deal with Djibril Sidibe's cross from the right and the ball fell kindly for Lemar, who lashed the ball into the roof of the net from the edge of the six-yard box.
The frustration was there for all to see as Kane picked up an unnecessary booking for a late lunge on Fabinho, but Spurs were handed a lifeline just before the break.
Alderweireld rose highest to powerfully head Lamela's corner into the back of the net to score his first goal in the Champions League since 2014.
The goal sprung Spurs into life as Lamela whipped in another dangerous ball, but Alli could not get on the end of it as the referee's whistle sounded for half-time.
With Pochettino obviously unhappy with his side's first-half performance, the Argentinian introduced Dembele at the break which allowing Alli to play further forward.
And the England midfielder was quick to make an impression, forcing a superb save from Subasic after letting fly with a dipping volley from 25 metres.
Referee Gianluca Rocchi handed Fabinho a yellow card and for a moment appeared to have given a penalty when the Monaco players swarmed around in disbelief, only for order to be restored and the corner re-taken.
Kane then wasted his glorious chance with 12 minutes remaining, shooting straight at Subasic from 12 yards out after being teed up by substitute Vincent Janssen.
However, Monaco saw out the final few minutes to leave Wembley flat and Tottenham in desperate need of a result when they travel to CSKA Moscow on matchday two on September 27.