MANCHESTER, England -- Mason Greenwood has found scoring goals a little harder this season, but he popped up with a big one in a 2-1 win at Old Trafford on Sunday night.

Heading for a 1-1 draw against relegation-threatened Brighton with seven minutes to go, the teenager was in the right place at the right time to score a vital winner.

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For much of the evening it felt like United would be consigned to a result that could drag them back into the race for the top four. Instead, with eight games to go, Ole Gunnar Solskjaer's team are second, four points clear of Leicester in third. After scoring 10 Premier League goals last season, it was only Greenwood's second in the league this term, but with United's campaign still hanging in the balance, it was an important one.

"It's always difficult to play Brighton," said Solskjaer.

"We have had good results and we've had to earn them the hard way. We managed to find a way in the second half.

"I thought we started well but when they scored, after that we couldn't find our rhythm again and we needed half-time to compose ourselves and go again. Second half we played some good stuff. More runs in behind, more movement, better movement.

"Sometimes after international breaks it takes time, and then maybe the fireworks have to be lit at half-time."

Solskjaer, who picked Dean Henderson in goal ahead of David De Gea, has usually tried to ease the pressure on Greenwood since the 19-year-old broke into the senior squad, but the forward is now central to United's hopes for the rest of the season.

There are doubts about whether Anthony Martial will play again this season after suffering a knee ligament strain while on duty with France. Marcus Rashford, meanwhile, was forced off here midway through the second half after scoring to make it 1-1. Rashford previously pulled out of the England squad with a knee problem and didn't look comfortable as he walked straight down the tunnel after being replaced by Dan James.

With Edinson Cavani struggling for form and fitness -- he's not scored for nearly two months -- it leaves the responsibility in front of goal squarely on Greenwood's young shoulders. And maybe he's finding his feet just when Solskjaer needs him most -- it's now two in two games after scoring in the 3-1 defeat to Leicester before the international break.

Greenwood started the season making headlines for the wrong reasons after being sent home by England, but there are signs he's ready to end it in the same fine form he enjoyed in his debut campaign.

"Mason Greenwood needs to add those goals to his tally because we know how wonderful a talent he is, and when he can add those goals we know he'll be a good one," said Solskjaer.

"Today he was one of our brightest players. He was clean, he was tidy and he got the goal. It's a header inside the 6-yard box and that's what we need more from Mason."

United are limping towards the finish line of a long, arduous season which could yet end in boom or bust. Finish second and win the Europa League and Solskjaer will have no problem arguing progress but it is not yet a given. Tiring and with injuries mounting, they haven't won three games in a row since December. There have been impressive performances at Manchester City and Milan but there have also been significant setbacks, few bigger than the FA Cup exit at the King Power Stadium.

When Danny Welbeck scored his fourth goal against United to give Brighton the lead here, it looked like there might be another. Even after Rashford had equalised, Brighton had a strong penalty shout turned down when Harry Maguire bundled over Welbeck in the 6-yard box.

United struggled to make many clear chances but when Paul Pogba skewed a shot across goal, Greenwood stooped to head in. Even during a dire first half, he looked most likely to score and was unlucky to hit the post with a fierce drive from the right-hand side of the penalty area.

"It was a hard night," said Greenwood. "When they scored the first goal we knew we had to react and put in a better performance. Everyone was excellent in the second half.

"I don't think we started very well but we knew we had to switch on and be focused. We should have started that from the moment we came out, but it's a good three points. There was a lot of men behind the ball and we had to have that creative spark.

"It's a confidence booster, I've not scored as many in the Premier League."

Solskjaer will need a few more from him if United are going to end their season on a high.