Despite walking out to a rapturous 'home' reception from a sold-out crowd at Wembley for their first Champions League tie since 2011, Tottenham Hotspur failed to channel their fans' energy into a fitting performance with a sluggish and mal-coordinated early display that ultimately cost them all three points against AS Monaco, despite an encouraging second-half fightback.
Mauricio Pochettino opted to field an intriguingly attacking side for the tie, with Dele Alli lining up in the pivot next to Eric Dier and Son Heung-Min, Christian Eriksen and Erik Lamela all slotted into the attacking band behind Harry Kane. Dele frequently stayed high up the pitch in both attack and defence throughout the first half, with Eriksen dropping in behind him to start attacks from deep. This approach almost bore fruit with an early chance that saw Eriksen initiating a gorgeous passing move from his own defensive half, culminating in a sumptuous cross from Harry Kane which Son looked to have converted, only to see his shot cleared off the line by a Monaco defender.
The obvious downside of Tottenham's starting formation was the team's vulnerability on the break, which soon told in the 15th minutes as a sloppy pass from Lamela in midfield saw Bernardo Silva sprung down the right flank. With Vertonghen standing too far off him by a yard or two, Silva was able to lash home a sucker-punch opener for the visitors.
Lamela almost atoned for his error immediately with a curling shot on 16' that was well-saved by Subisic, but it was Monaco who were next to celebrate again as Thomas Lemar found space to lash home from six yards on 31' after two Spurs players collided trying to deal with a cross.
After dominating the early stages on the game, Spurs looked set to stagger out at the half in an unsalvageable state. In the 45th minute, however, Toby Alderweireld stepped up to the plate once again to grant his side some breathing space by converting a pinpoint header from a Lamela corner. Spurs then almost dug out an immediate equaliser as a beautiful Lamela cross was plucked off Alli's toe by Subisic on the stroke of half time.
Pochettino more or less managed to fix the broken aspects of his starting system by substituting Mousa Dembele on for Son for the second half. With Moose patrolling the halfway line and Alli freed up to cause havoc with his jinking runs in the opposition third, Spurs seemed to find it easier to pen Monaco in and create openings. Kane had a shot blocked from just outside the six-yard box after being sprung by a beautiful ball from Dele Alli on 51', prompting a flurry of corners and chances for Tottenham.
Despite the near-constant second-half pressure, however, Spurs ultimately failed to carve out the killer opening required to level the game. Their best chance came on 79' as Vincent Janssen (introduced minutes earlier in place of Erik Lamela) somehow managed to chase down a hopeful long pass into the box and square for Kane, who mystifyingly opted to switch the ball over to his left foot and shoot directly at the keeper from 12 yards out. An ultra-attacking switch of Moussa Sissoko for Eric Dier failed to inspire the side to carve out a better opportunity, leaving the the Tottenham players to face up to a jarring defeat at the final whistle.
Ultimately, this match wasn't really anything to panic over. Pochettino will (hopefully) take away some clear lessons about the advisability of an Alli-Dier starting pivot from the game, and it's unlikely that we'll see the Spurs defence give up many more goals this season as soft as Monaco's two today. For the legions of Spurs fans who turned up at Wembley and tuned in across the globe for the team's first Champions League foray in five years, however, these conclusions will provide scant consolation at the end of a much-anticipated but ultimately bitterly disappointing evening.