Early Doors gave trainer Joseph O'Brien a first Galway Plate victory as Mark Walsh produced a perfectly-judged ride to hold off favourite Royal Rendezvous.
The West's Awake moved ahead after the second last but the JP McManus-owned horse's burst after the final fence saw him win by three-quarters of a length.
Paul Townend's run on Willie Mullins' 4-1 favourite came just too late.
Early Doors was priced at 7-1 with another Mullins horse Cabaret Queen third at 33-1.
O'Brien, whose father Aidan has already achieved Derby triumphs both at Epsom and the Curragh this summer, is proving to also be a successful trainer on the flat and over the jumps.
The trainer's latest Galway victory saw him emulate his father whose Life Of A Lord achieved back-to-back triumphs in the prestigious two-mile-six-furlong handicap during the 1990s.
After charging into the lead after the second last, The West's Awake faded in the run-in to take fourth at 66-1 for veteran trainer Edward O'Grady with Liam Cusack's 22-1 shot Snugsborough Benny completing the first five.
Early Doors a previous Cheltenham winner
Early Doors' previous wins included last year's Martin Pipe Handicap at the Cheltenham Festival over hurdles but Wednesday's race was only his fourth outing over fences.
He had been runner-up in three of those races but his favourable 10-5 Galway weight meant he was fancied in the betting and so it proved.
"I was tracking the lads going to the second last and we were proper motoring but he missed it and they got away from me a bit," said winning jockey Walsh.
"It gave me something to aim at coming up the hill. He galloped all the way to the line.
"It is a brilliant race and it is unfortunate the owners and crowd can't be here to see it."
The Galway Plate is the big race of the week long summer festival which continues through to Sunday at the Ballybrit venue.
The Galway festival is traditionally one of the most well-attended events in Ireland's sporting calendar but the Covid-19 pandemic meant organisers had to take the decision to hold the meeting behind closed doors.