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By Ian Ransom
Jan 15 (Reuters) - Marnus Labuschagne rode his luck to a home-ground century as Australia exploited India's injury woes and punished their poor fielding to reach 274 for five at the close of a steamy day one of the fourth test decider in Brisbane on Friday.
Captain Tim Paine was 38 not out and all-rounder Cameron Green on 28 at stumps, with Australia holding sway after winning the toss and batting on a Gabba pitch that flattened obligingly for the batsmen under a blazing sun.
It was a bad toss to lose for Ajinkya Rahane's decimated side, shorn of pace spearhead Jasprit Bumrah and spinner Ravichandran Ashwin, and stitched together with four injury-forced changes.
Selectors spread the load with a rookie four-prong pace attack, but it was soon a man down when seamer Navdeep Saini went off the field with a groin injury after lunch.
He exited straight after inducing a nick from Labuschagne that was dropped in the gully by Rahane when the batsman was on 37.
Labuschagne was then dropped on 48 before tea and duly made India pay in a 113-run partnership with Matthew Wade (45) before getting out slogging for 108.
"They probably played one extra bowler than they would usually, it could make a difference if we bat really big and we keep their bowlers out there," Labuschagne told reporters.
"It's definitely a mental challenge at this stage of the series and the way things are."
India blew a third chance late in the day, with Green reprieved on 19 by paceman Shardur Thakur, who grassed a waist-high caught-and-bowled chance.
For all that it could have been much worse for the tourists, who had held Australia to a courageous draw in the third test in Sydney to keep the series level at 1-1.
NEW BOYS
The home side were also wasteful, with four of their batsmen dismissed due to poor shot selection, and only opener David Warner (1) falling to a good ball when he nicked Mohammed Siraj to the slips in the first over.
Without a single first-choice bowler available -- all sidelined or long since departed with injuries -- India blooded two debutants in paceman T. Natarajan and spin-bowling all-rounder Washington Sundar.
Both the new boys had their moments.
Sundar claimed Steve Smith (36) as his first test wicket when the master batsman chipped a half-volley to short mid-wicket, while Natarajan, completing his hat-trick of debuts in all three formats, grabbed the wickets of Labuschagne and Wade. L4N2JQ1GJ
India's pacemen owned the first hour, dismissing both openers before the drinks break, with Thakur taking Marcus Harris for five when the recalled opener spooned a catch to square leg.
Smith's wicket raised India's spirits again but they were soon deflated by Labuschagne as he attacked with gusto after tea, bringing up his fifth test century with an all-run four and a glorious cover drive.
Soaking up the cheers of fellow Queenslanders in the terraces, Labuschagne ripped off his helmet and kissed its crest.
Unusually for a Gabba pitch, it presented with cracks that grew clearer as the day wore on, though there were few gremlins for the batsmen.
Australia will be confident of building on their total and then seeing whether the cracks might offer more for their pacemen at a ground where the home side is undefeated since 1988.
Under drastic circumstances, Sundar felt India's bowlers did a good job.
"We felt the wicket was good for batting," he said. "There was little bit of spongy bounce till lunch but after that the wicket was very good to bat." (Editing by Peter Rutherford)