A comical first-half own-goal from Lucas Bergvall has consigned a lacklustre Tottenham to a 1-0 loss away to AZ Alkmaar in the first leg of their Europa League last-16 tie. Bergvall's sliced clearance from a Troy Parrott shot looped in after 18 minutes and it proved enough to give AZ a first victory over an English side in 12 attempts. Spurs had eight days to prepare for this fixture but produced a flat display in the Netherlands and did not register a shot on target until the 88th minute. It was a thoroughly disappointing performance from Ange Postecoglou's team, especially given this competition remains the club's last hope of silverware this term and their only chance to salvage a difficult campaign. Tottenham now have it all to do ahead of Thursday's second leg in north London. Postecoglou resisted the temptation to start fit-again trio Micky van de Ven, Cristian Romero and Dominic Solanke and the injury curse actually struck the hosts as Mayckel Lahdo was forced off after eight minutes at AFAS Stadion. It contributed to a disjointed start, but AZ, with the first legitimate chance of the match, took the lead in bizarre fashion in the 18th minute. Peer Koopmeiners' corner picked out ex-Spurs forward Parrott, who had a side-footed shot which Bergvall completely miscued and watched in horror as his attempted clearance looped over Djed Spence and into the net. It was an embarrassing own goal and, while Tottenham briefly responded, Parrott was involved again soon after as Archie Gray blocked his effort before Ernest Poku sent the follow-up well wide. An even better opportunity was created after 31 minutes when AZ broke after a Son Heung-min chance and Parrott was played through, but Guglielmo Vicario raced out to brilliantly deny the Republic of Ireland forward. A poorly-worked short free-kick by Son summed up Spurs' half before the visitors survived a goalmouth scramble as James Maddison slid in to deny David Moller Wolfe, and Bergvall blocked from Koopmeiners. It remained 1-0 at half-time, but Postecoglou reacted by bringing on Wilson Odobert for Mathys Tel and Tottenham's urgency improved, with Bergvall firing wide before Son blazed over. AZ remained a threat and Poku forced Vicario into another save after a dangerous cross by Moller Wolfe. Rodrigo Bentancur was booked soon after for a late challenge on the excellent Parrott, which rules the Spurs midfielder out of next week's second leg. Chances remained at a premium for Tottenham and Postecoglou made a triple substitution with 18 minutes left, with Pedro Porro, Pape Sarr and Solanke sent on. It failed to spark a late rally and, although Odobert tested Rome-Jayden Owusu-Oduro for the first time in the 88th minute, Spurs were dealt a fresh blow late on when Solanke limped off after he was caught by AZ's goalkeeper. Absentee-hit Manchester United were unable to turn a positive performance into victory as Mikel Oyarzabal's penalty saw Real Sociedad head to Old Trafford with the last-16 tie poised at 1-1. Joshua Zirkzee put United into a deserved lead, only for Oyarzabal to level from the spot with Sociedad's first shot on target after the VAR spotted a Bruno Fernandes handball. Aritz Elustondo produced blocks to deny Fernandes and Zirkzee in quick succession, with the latter making the breakthrough in the 57th minute when firing home from the edge of the box. La Real offered little by way of response, but the VAR's intervention gave them the chance to level with 20 minutes remaining. Fernandes' handball was punished upon review and Sociedad skipper Oyarzabal scored from the spot. The rejuvenated hosts ended on top as United's lack of options and recent exertions took their toll, but they head back to Old Trafford for next Thursday's second leg in a decent position. Rangers took a big step toward the quarter-finals by stunning José Mourinho's Fenerbahce 3-1 in Istanbul, while Malick Fofana scored a brace as Lyon defeated FCSB 3-1.