Richard Dunneâ€™s second-half strike was enough to secure second place in Group B after Vasily Aleksanyanâ€™s clumsy own-goal gifted the home side the lead just before the interval.
Ireland boss Giovanni Trapattoni will now face an anxious wait to discover if captain Robbie Keane will win his race to be fit in time for next month’s play-offs.
The Italian manager’s decision to leave out in-form West Brom striker Shane Long was the main talking point ahead of Aremnia’s visit, with Trapattoni opting to partner Kevin Doyle with 24-year-old forward Simon Cox.
Cox repaid his manager’s faith with an impressive peformance and he was involved in the turning point of the game, when Armenia goalkeeper Roman Berezovsky was controversially sent off in the 30th minute after he was adjudged to have handled the striker’s attempted lob outside the area.
The visitors were forced to introduce uncapped stopper Arsen Petrosyan – and Ireland seized their chance to make the man advantage count by taking the lead in the 42nd minute.
Damien Duff’s cross was met by Doyle and the striker’s innovative backheel was inadvertently turned into the Armenian net by Aleksanyan.
Cox continued to impress after the break and he manufactured a chance for Stephen Kelly, but the right-back had his tame effort blocked. Moments later Keith Andrews fired an effort just over the crossbar.
And the continued Irish pressure paid dividends after 59 minutes when Petrosyan flapped at Aidan McGeady’s whipped cross and Dunne bundled home his first international goal in two years.
But the two-goal cushion was immediately halved as midfielder Henrikh Mkhitaryan fired a low effort past Shay Given, ending Ireland’s run of eight games withou conceding and setting up a nervy final 30 minutes in Dublin.
With Keane already a doubt for the play-offs, Trapattoni would have been keen to ensure his other first-choice striker Doyle was available for selection – but the Italian chose not to withdraw the Wolves forward, instead opting to replace Cox with Mark Walters.
The decision backfired when Doyle was shown a second yellow card for an elbow on Mkrtchyan, ruling the Wolves striker out of the first leg of next month’s play-offs.
Ireland: Shay Given, John O’Shea, Stephen Kelly, Richard Dunne, Sean St Ledger, Glenn Whelan (Keith Fahey, 77), Aiden McGeady (Stephen Hunt, 68), Keith Andrews, Damien Duff, Kevin Doyle, Simon Cox (Jonathan Walters, 80)
Armenia: Roman Berzovski, Sargis Hovsepyan, Valeri Aleksanyan, Hrayr Mkoyan, Edgar Malakyan (Arsen Petrosyan, 29), Henrikh Mkhitaryan, Karlen Mkrtchyan, Levon Hayrapetyan, Yura Movsisyan, Marcos Pineiro Pizzelli (Edgar Manucharyan, 53), Gevorg Ghazaryan (Artur Sarkisov, 62)
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