Tendulkar, in Mumbai colours after three years, came in at no 5 and batted fluently after starting cautiously against a largely inexperienced Raileays attack to reach his hundred off 103 balls with 14 fours and 3 sixes.
In all, the senior India batsman, whose last hundred in any form of the game was his unprecedented and much-feted 100th international century at Dhaka on March 16, struck 21 fours and three sixes during his 136-ball knock before edging medium pacer Anureet Singh to the slip cordon, three overs before stumps.
The 200-run partnership between Tendulkar, who batted for just over three hours, and one down Rahane placed Mumbai in command in their opening Group A fixture at the Wankhede Stadium here.
Rahane, who fully utilised the life given to him on seven by Murali Kartik, faced 203 balls and struck 13 fours during his unconquered knock. Giving him company at close of play was Abhishek Nayar, who is yet to open his account.
The cynosure of all eyes on day one of the match was clearly Tendulkar. The 39-year-old senior batsman's form in the last Test series against New Zealand at home was a cause for concern as he was bowled three times in as many innings.
But the script was tottaly different today, albeit at a lower level of competition.
The three-figure innings was his 18th in the championship and his 79th in first class cricket and it placed him within striking distance of overhauling Sunil Gavaskar's domestic record of 81 tons in games lasting three or more days.
