McClean’s 48th-minute strike settled a hard-fought game in which Ireland were forced on to the back foot for long periods, but hit their hosts ruthlessly on the break to silence the locals at the Ernst Happel Stadium.
The victory leaves the Republic with ten points out of 12 from their opening four qualifiers and firmly in the Group D mix ahead of their showdown with Wales in Dublin in March, a game which key man Robbie Brady will miss through suspension.
The forecast 20cm of snow overnight in Vienna thankfully failed to materialise and Martin O’Neill’s injury problems abated, with McClean able to start after recovering from a back problem, while there was a competitive debut for fellow midfielder Harry Arter, putting to bed rumours that he could opt for England instead.
There were returns from concussion and suspension respectively for Brady and Jeff Hendrick, but with Shane Long and Daryl Murphy both injured, a shortage of strikers meant a start up front, rather than the usual auxiliary midfield role, for Jonathan Walters.
In the event, Walters was to see rather too little of the ball where it mattered during an opening 45 minutes dominated by the home side, who knew anything but victory could prove hugely damaging to their qualification hopes.
For all their greater share of the possession, however, Austria were unable to create clear-cut chances until a flurry of activity just before the break.
Marcel Sabitzer was unfortunate to see his delicate 39th-minute chip over the advancing Darren Randolph come back off the bar and Walters clipped the top of the bar at the other end from Brady’s inviting cross.
Ireland returned after the interval knowing they would have to create more of a threat if they were to avoid a 45-minute onslaught, and it was they who broke the deadlock with less than three minutes on the clock.
Austria had resumed where they had left off, but were caught after losing possession deep in enemy territory and Wes Hoolahan exploited the space they had left behind to the full with a slide-rule pass which sent McClean racing in on goal.
The West Brom winger, who scored twice in Moldova last month, still had plenty to do, but his left-foot shot across keeper Ramazan Ozcan was unerring to send the 3,200 travelling supporters among a crowd of 48,500 into raptures.
Marc Janko should have levelled deep into injury-time, but headed criminally wide from Julian Baumgartlinger’s drive across the box as Ireland survived.