"We've won the cup and that's the most important thing for the team.
It was cruel on United who had dominated the first-half and deservedly led through Noel Hunt's scrambled opener. However, Rangers improved during the second-half and Boyd pounced on a slack Mark Kerr back pass with only six minutes left on the clock. In a gripping extra-time, Mark De Vries fired in United's second before Boyd squeezed in a late header to send the tie to penalties.
Boyd then held his nerve to net the winning penalty and Dundee United boss Craig Levein was understandably deflated.
"I thought we were magnificent today and suffered two sucker punches when we were leading," he told BBC Sport. "Twice it looked like we were going to clinch the game and we were hit by real body blows but we came back.
"All credit to the players, I thought they were fantastic. I feel for everybody associated with the club."