The Red Devils could end a six-year wait for any silverware on Sunday when they face Newcastle in the League Cup final.
But first comes the chance to land the scalp of Barcelona in a heavyweight Europa League clash on Thursday.
After an enthralling first leg at the Camp Nou, the sides are level at 2-2 as Rashford carried his carve-up of Premier League defences onto the European stage.
The England international turned a 1-0 deficit into a 2-1 lead for United in a seven-minute spell in Catalonia as he smashed home at Marc-Andre ter Stegen's near post then drilled in a cross that forced Jules Kounde to turn into his own net.
Another two goals in a 3-0 win over Leicester on Sunday that pulled United into Premier League title contention took his tally for the season to an already career-best 24.
But his explosion since the World Cup break is even more remarkable.
No player in Europe's top five leagues comes close to the 25-year-old's 20 goal involvements, with 16 goals and four assists since returning from Qatar.
"I don't feel like slowing down," said Rashford after leaving Leicester defenders trailing in his wake.
"I'm always looking to push and improve."
Out from Ronaldo's shadow
There is also a sense of a player making up for lost time.
After missing a penalty in England's Euro 2020 final heartache against Italy, Rashford badly struggled for fitness and form last season.
He was not the only one to disappoint in a disastrous campaign for United.
Ten Hag has transformed the mood around Old Trafford in his first season in charge -- but Rashford's return to form has been pivotal in a squad otherwise short on goals.
It is also hard to ignore that his hot streak has coincided with Cristiano Ronaldo's departure from the club during the World Cup.
Rashford has stepped out from the shadow of the five-time Ballon d'Or winner to become the player United fans dreamed he could become after bursting onto the scene as a fresh-faced teenager in 2016.
"I think as a manager, as a coaching staff we have to push them but finally it comes from the player," said Ten Hag on Rashford taking personal responsibility to deliver on his potential.
"When he loses focus then the scoring will stop. (That's) clear.
"He has so many skills, such high potential and I think there can be even more. When he works well, he will even score more goals because he can score with his left, right and his head."
The issue for United is what happens should Rashford fail to maintain his unparallelled scoring streak.
He has been an ever-present in United's 17 games in a brutal schedule since the World Cup.
There were signs of fatigue in how the visitors ended up clinging on for a draw in the closing stages at the Camp Nou last week.
But Ten Hag is counting on the crowd at the "Theatre of Dreams" to will his side over the line for what would be United's biggest European scalp since Rashford's penalty dumped Paris Saint-Germain out of the Champions League in 2019.
"Come Thursday, it is a big game, make sure you are there," said Ten Hag in an address to the supporters on Sunday. "We will beat Barcelona together."
