Real Sociedad's Mikel Oyarzabal coolly netted a penalty to hold Manchester United to a 1-1 draw in a Europa League last 16 first leg clash on Thursday.
The Red Devils are enduring a woeful season and winning the competition offers their only realistic route to Champions League football, but they could not protect their lead in San Sebastian.
Dutch forward Joshua Zirkzee netted his first goal in five games to send Ruben Amorim's side ahead at the Reale Arena before the hour mark but Bruno Fernandes conceded a penalty for handball, which Oyarzabal dispatched in the 70th minute.
The hosts came close to snatching a winner late on but Orri Oskarsson twice failed to finish and the match is evenly poised ahead of the second leg at Old Trafford next Thursday.
Amorim was left with just 18 players to call on because of an injury crisis, with Harry Maguire and Manuel Ugarte joining the likes of Amad Diallo, Kobbie Mainoo and Luke Shaw on the sidelines.
Up front the coach started with Rasmus Hojlund, who extended his barren run without a goal to 19 matches, while strike-partner Zirkzee now has two in his last 17 games.
The Portuguese coach said Wednesday it was not "crucial" for his team to win the competition but suggested it could turn around a dire season, with the club 14th in the Premier League and dumped out of the other cups.
The first half was a drab affair with neither side attacking with confidence or edge, although the Premier League giants came closest.
Real Sociedad defender Aritz Elustondo blocked Fernandes and Zirkzee shots as United shaded the first 45 minutes in San Sebastian.
Real Sociedad have endured a tough domestic campaign too, sitting ninth in LaLiga, but with the Europa League final at the home of rivals Athletic Bilbao, they would dearly love to win it at the San Mames.
Imanol Alguacil was able to bring back Takefusa Kubo, Oyarzabal and Luka Sucic after suspension and injury ruled them out of the 4-0 thrashing by Barcelona in LaLiga last weekend, but La Real struggled without injured midfield conductor Martin Zubimendi.
RAISED TEMPO
Fernandes sent a free-kick wide as United started the second half with more vim and Alejandro Garnacho fired into the side-netting when well placed.
The visitors made the breakthrough after 58 minutes when Zirkzee bundled home from Garnacho's pass across the area, with Real Sociedad goalkeeper Alex Remiro disappointed not to keep his effort out.
Brais Mendez fired wide from long range with Real Sociedad's first menacing effort midway through the second half.
A few minutes later the Basque side won a penalty when United captain Fernandes was adjudged to have handled in the area as he tried to clear a corner.
Oyarzabal, who scored the winner for Spain in the Euro 2024 final against England, dispatched it clinically, sending Man United goalkeeper Andre Onana the wrong way with his side's first shot on target.
The Cameroon international then made a good save from Mendez's long-range curler as La Real hit their stride.
Oskarsson should have won the game for Real Sociedad but poked a fine chance wide and had another effort well saved by Onana in the final stages.
The winner of the tie will face French side Lyon or Romanian outfit FCSB in the quarterfinals.
