The Red Devils headed into the game looking to try and return to winning ways after their 2-2 draw with Aston Villa last time out.
Manchester United also welcomed Spurs boss Jose Mourinho back to the Old Trafford dugout almost a year after he was sacked by the Red Devils.
Rashford was in fine form and he fired Manchester United into the lead in the sixth minute but Dele Alli equalised for the visitors in the 39th minute with a fine finish from inside the box.
However, Rashford made it 2-1 to the hosts when he dispatched his penalty in the 49th minute after having been fouled by Moussa Sissoko in the box.
Rashford has now scored nine goals and made four assists in the Premier League this season for the Red Devils.
And BBC Sport pundit Waddle was clearly impressed by what he saw from the England internatonal at Old Trafford on Wednesday night.
Speaking during BBC Radio 5 live‘s coverage of the game, Waddle said: “Tottenham are trying to work a way into the game but every time the ball goes to Marcus Rashford, you think something is going to happen.
“He is really in the mood tonight.”
Speaking just after Rashford had given Manchester United an early lead, Waddle said: “Absolutely top drawer.
“Sometimes Marcus Rashford goes missing in the game but he has everything in his locker to be a top player. It’s a fantastic strike and the goalkeeper is lucky it hit the crossbar.”
Rashford will be expecting to start for Manchester United when the Red Devils return to Premier League action with a trip to face derby rivals Manchester City at The Etihad on Saturday night.
Wednesday night’s win was just their fifth in the Premier League this season and it left them in sixth place in the top-flight table.
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