MANCHESTER, England, Sept 20 (Reuters) - Manchester United ( MANU ) manager Ruben Amorim said his side must match the level of urgency they showed against Chelsea on Saturday if they are to keep on winning.

Having tasted victory just once this season going into the game, on the back of their lowest top-flight league finish last term since they were relegated in 1973-74, the pressure was on Amorim ahead of Chelsea's visit in the Premier League.

The early dismissal of Blues goalkeeper Robert Sanchez gave United the platform to earn a vital win with goals from Bruno Fernandes and Casemiro but the performance, from the off, reached levels of intensity that had been lacking in recent struggles.

"Sometimes we have some moments that we feel an urgency to have a result," Amorim said. "Today we won, it's nice to win, but let's not forget that return to that urgency in our game.

"We need to win the next game. That is the most important thing. In this big club it's not a feeling that today is a really good game, let's relax a little bit. Let's keep that urgency. That is the most important feeling we have to take for the next week."

In true United fashion, the hosts still made things difficult for themselves from a seemingly unassailable position, 2-0 in front with a numerical advantage in the driving Manchester rain.

Casemiro's sending-off late in the first half gave the visitors a lifeline, with Trevoh Chalobah's header ensuring a nervy finish at an expectant Old Trafford.

"We showed that when everything is going well, we arrange something to make it difficult," Amorim said. "But we suffered together in the end. That was a good thing, if you look at the game we deserved to win.

"We were trying to do things a little bit too much, making a tackle that maybe we shouldn't. It's hard to say, because that is the pressure. I feel more pressure in some young guys sometimes.

"Maybe it's because Casemiro cares. We score one and he has that tackle. Sometimes it's not the pressure, they wanted too much in that moment."