Austria have been shorn of three of their first-team regulars ahead of Saturday’s 2018 World Cup qualifier against the Republic of Ireland in Vienna.

Manager Marcel Koller has confirmed that injury has ruled goalkeeper Robert Almer, defender Sebastian Prodl and playmaker Zlatko Junuzovic out of the Ernst Happel Stadium encounter.

Bayer Leverkusen’s Ramazan Ozcan, who serves as a back-up keeper for both club and country, is set to make his first competitive start for Austria after Almer sustained a serious knee injury in Austria Vienna’s 3-3 draw against Roma in the Europa League last month.

Junuzovic is also sidelined with a knee problem, but in-form Alesandro Schopf looks a ready-made replacement.

Schopf shone in Schalke’s win over Werder Bremen at the weekend, scoring twice in the 3-1 victory.

Marko Arnautovic is likely to line up against some familiar faces on Saturday, with Ireland midfielder Glenn Whelan and forward Jonathan Walters team-mates of the mercurial striker at Stoke.

Arnautovic is anticipating a tough test but believes home advantage could prove crucial, telling reporters: “We will do everything to win this match, but it will not be easy.

“We know that Ireland were at the Euros, and qualified many times for big tournaments, and we know their quality.

“I know almost every player, because they play in England. It will be a tough game and we know that they have really good guys in their squad.

“We don’t really know if they will play more offensively or more defensively.

“We play at home in front of a big crowd and at home we know that we are able to achieve a lot.”

Martin Harnik, who missed Austria’s 3-2 defeat to Serbia in October, is available for selection and acknowledged the importance of gaining ground on their Group D rivals.

“With a win on Saturday, we can equal the Irish in points,” the Hannover winger said. “Therefore, we are under a bit of pressure.”

Watch Austria v Republic of Ireland on RTÉ2 from 4pm and listen on RTÉ Radio 1's Saturday Sport from 2.45pm.