Knock's Colin Fairweather and Laytown & Bettystown Thomas Mulligan clinched the Northern Ireland Open spots available at Tuesday's Northern Ireland Amateur Open at Galgorm Castle.
Fairweather defeated his fellow Irish amateur international Tiarnon McLarnon and Irish Boys international Mulligan in a play-off to win the amateur event.
With Mulligan the leading Under-18, he also earns an NI Open spot.
Fairweather's win came four days after he lost in the North of Ireland Final.
The Belfast man shot rounds of 72 and 74 to tie on four-over 146 with McLarnon (77, 69) and Mulligan (69,77).
Fairweather was leading by one playing the final hole in the 36-hole strokeplay event but lost his ball off the tee.
The 26-year-old eventually made a bogey six to force a play-off with Massereene's 2015 winner McLarnon and Mulligan.
The new champion didn't make the same mistake in sudden death after hitting a long drive down the fairway before firing a seven-iron onto the green to set up a two-putt birdie from 20 feet.
McLarnon missed a five-footer for his birdie, while Mulligan lost a ball off the tee, and though he still managed a par it was Fairweather who took the spoils.
"My putting wasn't up to scratch but I struck the ball very well and still managed to get it round. I'm over the moon to win here today and claim a place in the NI Open," said Fairweather, who will now tee it up alongside the professionals in the Galgorm Resort & Spa-sponsored Northern Ireland Open from 10-13 August.
Although Mulligan lost out in the play-off, the 17-year-old had already secured the second NI Open place up for grabs for the leading under-18.
"It's great, I came here to secure the under-18 invite," said the Leinster player, who also represented Great Britain & Ireland Boys in the Jacques Leglise Trophy in 2016.
This year's Northern Ireland Open introduces a new Shootout Sunday, which will see the leading 24 players after Saturday's action compete in six-hole strokeplay match play games in a knockout format.