Manchester United manager Ole Gunnar Solskjaer praised winger Daniel James and said he was confident a winning run would give his players the energy to get through a tough schedule after a 3-1 Premier League win over Newcastle United on Sunday.
United followed up Thursday's 4-0 Europa League win over Real Sociedad with a patchy performance against Newcastle, their goals coming from individual quality amid some shaky defending.
Making a rare start, James scored United's second to put them 2-1 ahead.
"Dan with the energy he has, the X-factor and the pace, he gives us something that must be hard to play against if you are a defender," Solskjaer told the BBC.
"He is working hard, he is a great boy in and around the place. He knows he has been very close a few times. When you score the amount of goals he has at the moment confidence must be sky high."
"Momentum? Just keep going. You have to be relentless. The season is a strange one but you have to build on confidence. We have to recover well in between and I am sure they will because when you win games you get energy."
Following the return leg against Real Sociedad at Old Trafford on Thursday, United visit Chelsea and Crystal Palace in their next two Premier League games.
Newcastle suffered an eighth league defeat in 10 games and remained dangerously close to the relegation zone in 17th spot and three points ahead of 18th-placed Fulham.
Their manager Steve Bruce conceded the Magpies needed to turn unrewarded solid performances into scrappy wins if they are to avoid relegation.
"I am convinced we will be safe, there are six or seven teams looking over their shoulders," Bruce told BT Sport.
"We need to win a few games. We have to get to that magical point mark - whatever it is. When you come here you've got to be good for 90 minutes. There were pleasing signs but you've got to turn pleasing signs into results."
(Writing by Zoran Milosavljevic; Editing by Ed Osmond)
