Chasing 189 for victory on a spicy pitch, India slumped to 39-4 but Rahul’s unbroken 108-run partnership with Ravindra Jadeja guided them home with 10.1 overs to spare.
Earlier, India’s bowlers, complemented by some excellent catching, bundled out Australia for 188 inside 36 overs at the Wankhede Stadium.
Mitchell Marsh, returning to international cricket after ankle surgery, smashed 81 off 65 balls but his exit triggered a collapse.
With India’s regular captain Rohit Sharma absent due to family commitments, Hardik Pandya won the toss and elected to field at the Wankhede Stadium.
By the second over, India had drawn first blood.
Travis Head, who made five, charged out against Mohamed Siraj but ended up deflecting the ball onto his stumps.
Marsh steadied the ship with a 72-run stand with Steve Smith, who is leading Australia in the absence of Pat Cummins who stayed back in Sydney following the death of his mother.
David Warner also missed the match through injury though Australia expect the opener to play in the next two ODIs.
Smith made 22 before Pandya removed him caught behind.
Pandya said: “We were under pressure in both the innings, but we kept our composure, and found ways to come out of those situations. When we got the momentum our way, we didn’t let it go. I am really proud the way we played today. Jaddu did what he was supposed to do coming back after eight months away from ODIs. I enjoyed my bowling and batting, would have loved to finish it off, but the way KL and Jaddu batted, it was calming to those watching from the outside.”
Marsh, in his first knock as an ODI opener, hit 10 fours and five sixes and Australia looked pretty comfortable at 129-2 in the 20th over before the wheels came off their innings.
Jadeja removed Marsh and took a stunning catch to send back Marnus Labuschagne (15) before Mohamed Shami’s triple strike derailed Australia.
Josh Inglish (26), replacing an unwell Alex Carey at wicketkeeper, dragged the ball onto his stumps, Cameron Green (12) had his off-stump uprooted and Marcus Stoinis (5) perished in the slip.
Glenn Maxwell made eight on his return from a broken leg and Mohamed Siraj (3-29) dismissed the scoreless Sean Abbott and Adam Zampa in successive overs as Australia folded in 35.4 overs.
Rahul said: “Three wickets had gone down, and Starc was swinging the ball. He is dangerous when it is moving. I gave myself some time, not go searching for runs. I was fortunate I got a couple of boundaries early on. Whoever I batted with, the talk was that there is a bit of help in the wicket, but we can’t go into our shell and look to play out a certain bowler. We wanted to run hard, we wanted to put the loose balls away. The minute a left-hander walked in, I got a few loose balls too.”
The Indian opener added: “That happens to the best of bowlers. Jaddu batted beautifully, he is in great form, and he knows what to do in those situations. When we started off, I didn’t think the pitch was going to help the bowlers that much. The minute Shami came back in, he did wonders. Any team that wants to win needs to pick wickets in the middle over. I enjoyed my keeping. When there is bounce, I enjoy it. When it is slow and slow, it is challenging physically.”
India’s start was even worse and their top four were back in the hut inside 11 overs after Mitchell Starc (3-49) struck three blows that included the prized wicket of Virat Kohli, who managed four.
Rahul added 44 runs with Pandya to arrest the slide and killed off the contest with his collaboration with Jadeja, who remained not out on 45, which included the winning boundary.
Austraoian captain Smith said after the match: “We weren’t expecting this when we rocked up here. India bowled well this morning, but we probably left a few out there. Had we got 250, we would have had some match. Mitch started really well. He took the game on early, and got a few away. Through the middle we lost a few too many wickets. We were always one partnership from them beating us, and Jadeja and Rahul did that. 260-270 was par. It was offering a fair bit for the seamers. The ball swung pretty much throughout. We just needed to score more runs. If we had got a partnership and take it deeper. It was not to be, and credit to India.”
The second match is scheduled in Visakhapatnam tomorrow, while Chennai hosts the final ODI on Wednesday.
India won the preceding four-Test series 2-1.
BRIEF SCORESAustralia 188 all out in 35.4 overs (M. Marsh 81, J. Inglis 26; M. Shami 3-17, M. Siraj 3-29) lost to India 191-5 in 39.5 overs (KL Rahul 75 not out, R. Jadeja 45 not out; M. Starc 3-49, M. Stoinis 2-27)
Result: India won by five wickets
Series: India lead the three-match ODI series 1-0