It was an almost perfect conclusion for 13th seed Gourlay who, after falling in the first round of last month's Potters Holidays World Indoor Championship, was in danger of losing his world top 16 status for the first time in well over a decade.
But the 44-year-old from Glasgow mounted a great run in Swansea, following victories over 2009 world champion Billy Jackson and the reigning world champion Paul Foster by edging past England's 2010 world champion Greg Harlow in today's other semi-final, by a 6-6, 6-5 margin.
After world No3 Royal won the opening end of the final, it was Gourlay who took the upper hand – going on to win the set by a single shot
But the second was all Royal as the Suffolk 36-year-old punched his way through to the best-of-three-ends tie-break decider.
By now Royal was on a roll, and the 2008 champion snatched the first two ends to claim a dramatic 6-7, 11-2, 2-0 victory.
"I've had a fantastic season because, although I'm officially ranked as number three in the world, my provisional ranking had slipped to 17 by the start of the winter season," said the two-time Welsh champion.
"Getting to the semi-finals of the world championship at Potters, and now winning the Grand Prix title in Swansea, means I have climbed the rankings, and have cemented my place in the top eight.
"I like it here in Wales," continued the beaming left-hander. "It's great to have won my second title here in four years - especially against such a great player as David Gourlay. I started slowly, and played a bad end to lose the first set, but dug deep and found some good form in the second set.
"On the fourth end, I played a gentle trail, moving the jack an inch or so to score three shots when David was holding shot. That filled me with confidence, and another treble on the next end pout me 9-1 in front.
"David played well in the tie-break, but I was able to find the right bowls at the right time to get over the line."
While Gourlay now boasts appearances in 15 World Bowls Tour singles events – more than any other player – he won his last title at the Scottish Masters in December 2002, since when the Scot has finished as runner-up on eight occasions.
"I'm disappointed to lose in yet another final - I think that's the sixth in a row," said the disconsolate Glaswegian. "But you can't take anything away from Mark, who produced some outstanding bowls in the second set - and again in the tie-break - and fully deserved to win."
RESULTS: Co-operative Funeralcare Welsh Grand Prix, Swansea, Wales
Semi-finals:
[4] Mark Royal (ENG) bt [1] Darren Burnett (SCO) 8-8, 7-4
[13] David Gourlay (SCO) bt [3] Greg Harlow (ENG) 6-6, 6-5
Final:
[4] Mark Royal (ENG) bt [13] David Gourlay (SCO) 6-7, 11-2, 2-0
