Rashford's deflected effort in the third minute of injury time was enough to give Manchester United victory over Wolves at Old Trafford and move them second in the Premier League.
The game seemed destined for a draw when Rashford took possession on the edge of the area, virtually next to the goal-line.
But after cutting inside the box, the England man let fly with a left-footed shot that deflected off Roman Saiss to leave Rui Patricio completely wrong-footed.
Rashford later said, "It's the deciding goal. Probably not the most beautiful but we will take what we can get and take the three points and move on.
"Today was tough but we expected a tough game but managed to get over the line.
"The full-back had cramp a few minutes before so I just had it in my head I wanted to go at him and make him chop and turn and just see if I could make something happen and thankfully in the end we got a deflection.
"It means a lot. We were a little disappointed that we didn't play as well as we wanted to or could have but it is three points and no matter how scrappy it was we will take it.
"For us, we can't look too far ahead. We are a team that is still doing a lot of work on ourselves. We have to take it one game at a time but if we can keep finding ways to win like this we will see where we are at the end of the season."