Virender Sehwag got the World Cup off to an explosive start with 175 as India spoilt Bangladesh's party with a resounding 87-run victory in Mirpur.
Sehwag added 203 with Virat Kohli, who scored 100 not out on his World Cup debut as India racked up 370-4.
Bangladesh, hosting their first World Cup match, faded after a rapid start to 283-9, Tamim Iqbal top-scoring with 70.
Seamer Munaf Patel took 4-48 as India gained revenge for their shock World Cup loss to the Tigers four years ago.
There was an atmosphere of feverish anticipation at the Shere Bangla Stadium but the home fans were given an immediate illustration of the size of the task facing their heroes when Sehwag leant back and effortlessly clouted the first ball of the innings through the covers for four.
That set the tone for a devastating knock, featuring 14 fours and five sixes as Sehwag compiled the joint fourth-highest innings in World Cup history.