Fourteen-man Westmeath did it the hard way as they pulled off a stunning triumph at Pearse Park in Mullingar yesterday.
Having lost a man before the game was even halfway through, the home side looked dead and buried when they fell six points behind. But a memorable display of pure passion and ravenous desire carried them through to a quarter-final crack at Galway.
Niall O'Brien, the pride of Castletown Geoghegan, was the star of the show, scoring eight points in a wonderful display of finishing.
The Saffrons failed to make effective use of their numerical advantage following the dismissal of Westmeath defender Conor Jordan, and their failure to respond to the home side's second-half revival must be a worry to new manager Jerry Wallace.
For Brian Hanley and his men, however, there's a glamour tie with the Tribesmen to look forward to, and who knows what they might conjure up in that one?
Neil McManus, a powerhouse at centre-back, got Antrim's challenge going with a long-range free, before Liam Watson broke free to slot over his first point of the afternoon.
It wasn't until the 17th minute that O'Brien opened Westmeath's account from a free, but the visitors turned it on again, with Shane McNaughton steering over two gems from wide on the left.
McManus sent another monster free between the posts as Antrim began to tighten their grip on the game. Westmeath corner-back Jordan, who had earlier been booked in an altercation with Watson, picked up a second yellow card on the half-hour, and the hosts faced a massive task.
They trailed by five at the break, after Watson's third point had shot Antrim into a 0-8 to 0-3 lead. But the 14 men of Westmeath took the game fearlessly to their opponents.
O'Brien continued to hit the target from frees, and two glorious scores from Francis Boyle raised their hopes. O'Brien's seventh score narrowed the gap to a point, and 10 minutes remained on the clock when Brendan Murtagh brought the sides level. O'Brien shot the Lake County in front for the first time in the 64th minute, and the deal was sealed by Murtagh's late score.
Scorers -- Westmeath: N O'Brien 0-8 (6f), B Murtagh (1f), F Boyle 0-2 each, A Clarke, J Shaw 0-1 each. Antrim: L Watson 0-4, S McNaughton (1f), N McManus (2f) 0-3 each, B McAuley, C McCann 0-1 each.
Westmeath: S McGovern; C Jordan, A Price, P Fennell; P Dowdall, A McGrath, P Greville; A Clarke, J Clarke; B Murtagh, F Boyle, R Greville; N O'Brien, J Shaw, E Price. Subs: D Fennell for Boyle (62), P Gilsenan for R Greville (72).
Antrim: DD Quinn; J Kerr, C Carson, A Graffin; M Gettens, N McManus, N McAuley; B McAuley, P Shiels; M Herron, B McFall, E McCloskey; D Hamill, L Watson, S McNaughton. Subs: K Stewart for Hamill (46), PJ O'Connell for Herron (56), C McCann for McFall (61), S McCrory for Kerr (67).
Referee: A Stapleton (Laois).