Romelu Lukaku scored his sixth Premier League goal of the season. (AFP/Getty Images)

Jose Mourinho has highlighted the importance of Romelu Lukaku after the Belgian’s first-half strike secured a 1-0 win for Manchester United over Southampton.

Lukaku met Ashley Young’s cross from the left flank with a header which was saved by Fraser Forster, but the 24-year-old managed to react quickest to the rebound to poke the ball into the net.

United were forced to defend in the second half as Lukaku and Ander Herrera missed chances to put the game beyond Southampton’s reach.

And Mourinho has praised his side for holding out for the victory at St Mary’s.

‘It was a hard game but I am really happy,’ Mourinho told Sky Sports.

Lukaku struck the winner for United in the first half. (EPA)

‘His [Lukaku’s] work is so important for us. He scored his goal and worked hard like everybody else.

‘Nobody feels the pressure to play always attacking football because so many teams play always defensively.

‘I felt some of the boys were not sharp. I didn’t feel like we could score three or four goals like we sometimes do so the option was to make sure we got the points.’

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