Opener Rohit Sharma (52), Virat Kohli (50) and Suresh Raina (49 not out) helped India reach 200-3 in reply to Australia's 197-5.Watson, who led after first-choice captain Aaron Finch was ruled out due to a hamstring injury, smashed six sixes and 10 fours off 71 deliveries.
Finch holds the record for the highest individual T20 score of 156, which he got against England at Southampton in 2013.
India had won the first game at Adelaide by 37 runs and the second at Melbourne by 27 runs.
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