Stevie Campbell's side stayed top of the Clydesdale Bank Premier League after a narrow, but deserved victory at Fir Park tonight.
Dale Hilson opened the scoring ten minutes into the second half with Ryan Ferguson curling in the second four minutes later.
Motherwell however immediately pulled one back through Craig Moore.
Then right on 90 minutes Jordan Moore sealed a fourth successive win with a third goal, despite the hosts pulling back another goal in the five minutes of stoppage time added on after Willie Robertson was stretchered off following a head knock with John Soutar. Both United players were subsequently admitted to hospital thoroughly spoiling an otherwise good evening for United's U-20s.
John Soutar was released on Monday night and it has been confirmed that Willie Robertson would be out for a few weeks with pulled muscles in the neck and shoulders.