Boyce opened the scoring in the all Premiership quarter-final tie with his 18th goal of the season, but McKay, who is on a season-long loan at Tannadice from Wigan, secured United’s semi-final spot when he headed home his eleventh of the campaign to set up a clash with Hibernian or Inverness Caledonian.
Also in the Dundee United squad on Saturday was Enniskillen-born Joe McGovern, brother of Michael, who was on the substitute’s bench and midfielder Paul Paton, whose recent impressive performances earned him the Scottish Premiership player of the month for February.
“It’s always nice to win an award,” said Paton, “But obviously the most important thing is that it was a good month for the club, even though we are still bottom of the table.
“We’ve got a lot of big games coming up, we’re still positive and confident and we’ll take that into those games.”
Elsewhere in Scotland Jordan Thompson, who is on-loan at Airdrie from Rangers, scored his first goal for the club and assisted in another as the Scottish League One recorded a 3-1 success at Cowdenbeath.
In England, Will Grigg was on target yet again for Wigan Athletic, however his 17tth goal of the season was only enough to earn the promotion chasing League One side a point at home to Peterborough United.
Milton Keynes Don midfielder Ben Reeves has had a torrid time with injuries this season, but he certainly made an impact at the weekend when just a minute after coming off the bench he scored a penalty to give the struggling Championship outfit a much needed 2-0 success over QPR.
Only Southampton’s Steven Davis and Gareth McAuley of West Brom were in action in the Barclay’s Premier League over the weekend.
Missing of course were Chris Brunt, who received the devastating news during the week that he is to miss the Euro 2016 Finals with a cruciate ligament injury, while both Jonny Evans (hamstring) and Craig Cathcart (calf) were also ruled out.