Realistically, that means Ireland are likely to have to win both their remaining games - against Moldova at the Aviva Stadium and the Welsh in Cardiff next month - to keep their dreams of a trip to Russia alive.

And that is just what they intend to do.

Walters said: "It's going to be a grandstand finish and we know what we need: two wins. We'll go for it.

"Look, it was pretty sombre in there after the defeat, but we know we've got a month to go. We meet up again and then we'll be right up for those two games.

"We have two games to go and hopefully we can do it."

Ireland have previous in that respect - they looked to be out of the race for Euro 2016 qualification until they put together a run of successive victories over Gibraltar, Georgia and world champions Germany to edge out Scotland, eventually making it to France via the play-offs.

They were similarly resilient at the finals too, booking their place in the knockout phase with a famous 1-0 win over Italy before giving the hosts a major scare in the last 16.

However, their task this time around looks even tougher. A difficult four days saw them return from Georgia with a fortuitous point on Saturday, when they turned in a poor display, and they then emerged from the clash with the Serbians empty-handed despite a vastly-improved performance.

Aleksandar Kolarov's stinging 55th-minute strike won the day on Tuesday, although Nikola Maksimovic's 68th-minute dismissal sparked a late onslaught during which Ireland were adamant they should have been awarded a penalty for Jagos Vukovic's clumsy challenge on substitute Daryl Murphy.

Walters said: "We threw the kitchen sink at them and couldn't get the result. Fair play to Serbia. It's going to be a grandstand finish and we know what we need, two wins. We'll go for it.

"We had some half-chances, shots from the edge of the box that didn't hit the target. We probably should have had a penalty, but it wasn't to be.

Gutting result for Ireland tonight but a much improved performance and there's still two games to go and a chance to qualify #IREVSER pic.twitter.com/umgZLriKfv

— Inpho Photography (@Inphosports) September 5, 2017

"They're a very difficult side, the way they play the game and waste a bit of time. They're 1-0 up, so they were always going to put men behind the ball.

"They've got big boys and they're clever in what they do, going down quite easily. They got free-kicks you probably wouldn't get in England.

"But it doesn't matter how you perform if you don't get the points. It wasn't to be. We go again, Moldova here and then the big one in Wales. We'll see what's to be and hopefully we can put in performances like that and get the right result."

Bottom-of-the-table Moldova, who have only two points to their name but held Wales for 80 minutes in Chisinau on Tuesday evening before succumbing 2-0, are due in Dublin on October 6. Ireland midfielders Robbie Brady and James McClean will sit out that match through suspension, in Brady's case serving a ban for the second time in the campaign.

Ireland travel to Cardiff three days later, desperately hoping qualification is still a possibility when they get there.