Republic of Ireland 1-0 Germany: Shane Long's winner against world champions revives O'Neill's men
Republic of Ireland manager Martin O'Neill saluted his "super-sub" Shane Long after the Southampton striker's goal sealed victory over world champions Germany.
Long came off the bench to blast the Republic firmly into the race for Euro 2016 qualification with a famous victory.
The Saints' striker beat Manuel Neuer with a thunderous right-foot shot 20 minutes from time to secure a 1-0 win which sends them to Poland on Sunday still in with a chance of automatic qualification from Group D.
Germany dominated for much of the game but a combination of poor finishing and heroic defending allowed the home side to see out time and they have secured at least a play-off place.
O'Neill will now take his side to Poland knowing victory will secure their passage to France.
He said: "Shane has come on against Poland (in March) and proved his worth (with a late equaliser), and I think at this minute the role suits him.
"When I get into the dressing room I'll say 'well done' to him because he's won the game for us."
Long may disagree with his manager's assessment, having minutes earlier expressed his disappointment at not starting the game.
He said: "I was upset but there are 25 players who all want to start. Everyone's putting pressure on the starting XI.
"The manager called me with 60 minutes gone and told me to go on and make an impact. I felt I could cause trouble on the break and thankfully I did that."
Joachim Low's men dominated possession, but they failed to do a great deal with it as Ireland keepers Shay Given and Darren Randolph, who replaced the injured 39-year-old two minutes before the break, did not have a single save of note to make.
Long replaced Murphy almost immediately and the newcomer had only five minutes to wait for his big moment, running on to Randolph's clearance and hammering the ball past the stranded Neuer to raise the roof at the Aviva.
Daryl Murphy might have given the Republic the lead on 64 minutes when he blasted a long-range effort just wide of the upright after Wes Hoolahan's initial shot had been blocked by Mats Hummels.
O'Neill seemed lost for words as he reflected on a momentous win for his side.
"It's an absolutely fantastic win," he said.
"We showed bravery in the second half and had to withstand a lot of pressure. We have beaten the world champions tonight and that shouldn't be taken away from players.
"We have a big match against Poland now but one way or another, at least we've reached the play-off and we've something to go for on Sunday."
Captain John O'Shea added: "We wanted to get it back in our hands and now we've stepped up again tonight and showed we can go on to get automatic qualification.
"(Poland have) got some good players but we've shown tonight we can mix it with the best."
Republic of Ireland: Given (Randolph 44), Christie, Keogh, O'Shea, Ward (Meyler 69), Hendrick, McCarthy, Brady, Walters, Hoolahan, Murphy (Long 65).
Goals: Long 70.
Germany: Neuer, Ginter (Bellarabi 77), Boateng, Hummels, Hector, Reus, Gundogan (Volland 85), Kroos, Ozil, Muller, Gotze (Schurrle 35).
Referee: Carlos Velasco Carballo (Spain).