With Robbie Smith excelling throughout at full-forward, Longford qualified to play Laois in the last eight after a one-point win in this first-round replay against Westmeath at St Loman's Lakepoint Park in Mullingar.
The game was spoiled by driving wind and heavy rain from start to finish.
Accordingly, the match never came close to replicating the thrilling draw in Pearse Park a week earlier.
Westmeath had the aid of the prevailing wind in the first half, but, in truth, the conditions made it very difficult for either side to create scoring opportunities.
However, against the odds, both sides managed to kick one terrific score apiece in this opening period – Rory Connor's 20th-minute point being matched a minute later by Dean McNicholas at the other end of the pitch.
Robbie Smith and Ray Connellan were both accurate from placed balls, while the only clear goal chance fell to Westmeath's Dean McNicholas deep into added-time, but Garret Higgins pulled off a great save.
Ultimately, Westmeath managed to carve out a lead of 0-5 to 0-3 at the interval.
Three great points (including one free) from the outstanding player on view – Smith – put Longford on level terms (0-6 each) by the 38th minute, with the home team's only score in that period coming from Lorcan Dolan.
Both of Smith's points from open play were from over 40 metres and were of the highest quality, considering the conditions.
It was tit-for-tat for the next 15 minutes, with Westmeath substitute Eoin Monaghan scoring both his side's points, with James McGivney and Smith (another free) being on target for the winners.
Longford captain Barry McKeon, who had been black-carded in the drawn game, emerged as his side's hero when he kicked the winning point in the 57th minute and there was no way back for Westmeath as the ref blew the final whistle to send Longford into the quarter-finals.
Scorers – Longford: R Smith 0-6 (4fs), R Connor, J McGivney, B McKeon 0-1 each. Westmeath: E Monaghan, R Connellan (2fs) 0-2 each, S Dempsey (f), D McNicholas, L Dolan, J Donoghue 0-1 each.
Longford – G Higgins; C Farrelly, A Farrell, A McBrien; S Clarke, S McLoughlin, C Shields; B McKeon, J McGivney; E Noonan, R Connor, P Kiernan; A Dalton, R Smith, L Connerton. Subs: R McNerney for Connerton (52), D Mimnagh for Kiernan (56).
Westmeath – M McMahon; J Rock, K Daly, J Donoghue; D Lynch, P Holloway, D Whelan; D McNicholas, D McCormack; L Dolan, S Daly, A Coffey; G Leech, R Connellan, S Dempsey. Subs: E Monaghan for McNicholas (34), M Rock for Leech (56).
Ref – F Barry (Kildare).