Ganguly's Hundred Powers India to 306-5
Ganguly hit eight fours and six sixes in his punishing 152-ball knock.
He and Rahul Dravid, who made 62, gave India the platform for their big score with a 175-run second wicket partnership from 217 balls.
Runs came in a torrent toward the end of the innings, 110 being raised from the final 10 overs.
Ganguly started cautiously after the early loss of Sachin Tendulkar to young paceman Travis Friend for eight.
Ganguly, playing his 156th one-day game, hit opposing skipper heath streak for three of his eight fours and hoisted leg spinner Brian Murphy, Viljoen and offspinner Marillier for two sixes each.
He was eventually dismissed in the 45th over, caught by Douglas Marillier at point as he tried to heave left-arm spinner Dirk Viljoen for another boundary.
But Sunil Joshi (22) and Hemang Badani (17 not out) kept the runs flowing.
Dravid completed his 29th one-day half-century before being run out by a direct throw to the non-striker's end by streak fielding at mid-on.
Friend, 19, was the most economical of the Zimbabwe bowlers, conceding just 37 runs from his 10 overs.
(Reuter)