FA Cup finalist United was without Romelu Lukaku and Alexis Sanchez due to injury and its attack looked blunt without the duo, with Brighton the better side throughout at the Amex Stadium on Saturday.

David de Gea, crowned United's player of the year for the fourth time this week, eclipsing Cristiano Ronaldo's club record, made a string of saves to keep his side level during the first half.

But Gross nodded in a Jose Izquierdo cross after the break to score his seventh top-flight goal of the season, Marcos Rojo unable to clear the effort before it crossed the line, to guarantee Brighton will stay in the Premier League.

Chris Hughton's men had been beaten twice by United this season without scoring, but ending a six-game winless run in the Premier League moves them up to 11th.

Jose Mourinho, meanwhile, will be concerned by his side's lack of incision and quality in the final third, with a Wembley clash against former club Chelsea just two weeks away and second place not yet certain.