Manchester United secured a vital three-point haul at home to Real Sociedad on Wednesday thanks to an Inigo Martinez own goal in the first minute of the game.
Both sides traded blows, Antonio Valencia and Antoine Griezmann hit the post and Wayne Rooney missed a glut of chances in a relatively even contest.
The loss leaves la Real almost no chance of qualifying from the group, but United move into pole position.
Jagoba Arrasate's side started in horrific fashion, allowing United to move through the gears quickly and fashion a chance on the left-hand side.
Patrice Evra fed Rooney and after wonderful work inside the box, he smacked a shot against the far post. With players scrambling to retrieve the second ball, Martinez inexplicably slotted it into his own net.
With United's minutes to goal ratio at 1:1, the home crowd found their voice and David Moyes' side immediately settled in and took control of proceedings.
The right side was particularly fruitful through Antonio Valencia and Rafael, and a succession of crosses found Rooney, but the England international failed to double his side's tally.
Javier Hernandez saw a headed goal disallowed shortly after for offside and it was only then that la Real finally appeared to settle in.
Arraste's side tested David De Gea for the first time as Haris Seferovic's vicious strike was palmed over, then Antoine Griezmann smacked the post from 25 yards from a free-kick conceded by Rafael.
La Real started the second half on fire, with Griezmann nicking the ball into Vela's path, but the Mexican's outstretched toes just failed to make contact from 10 yards out.
What followed was an avalanche of Sociedad attempts on goal, with Seferovic, Xabi Prieto and David Zurutuza all firing goalward and forcing blocks from De Gea and co.
Man United responded with a volley of their own, forcing wonderful saves from Claudio Bravo and hitting the post via Valencia. Shinji Kagawa then fluffed his lines as he bore down on goal and Rooney fired well over when put through on goal.
The final 10 minutes were stretched as both sides went for the jugular and United really should have scored another as Ashley Young, Rooney and Valencia were denied yet again by Bravo.
A nervy finish, but three points in the bag for Moyes.
Key Player Grades
Antonio Valencia, Manchester United: A
Valencia was back to his best form, firing in accurate crosses, creating opportunities and hitting the post with a firm effort.
Antoine Griezmann, Real Sociedad: A/B/C
Real Sociedad took a while to get going but once they starting playing, Griezmann was central to every move. Tricky, silky and quick.
Full Player Grades
|David De Gea||GK||B+|
|Alberto De la Bella||LB||B-|
Manchester United host Stoke City at Old Trafford, while Real Sociedad welcome Almeria to Anoeta.