Tottenham must beat AZ next week to keep their faint silverware hopes alive after Lucas Bergvall's freak own goal gave the Dutch side a 1-0 lead in their Europa League last-16 tie.
Despite resting Heung-Min Son and Djed Spence in their last game against Manchester City eight days ago, Spurs' freshness did little to help them as their hosts dominated from start to finish and were unfortunate not to win by a greater margin.
Despite AZ's superiority, the first leg was only settled by Bergvall's unfortunate intervention 18 minutes in, when he swiped at a corner and looped the ball over a hapless Guglielmo Vicario and in for the hosts' winner.
With their season now entirely dependent on their success in the Europa League, next Thursday's return leg at the Tottenham Hotspur Stadium now becomes a win-at-all-costs encounter for Ange Postecoglou and his side.