Southpaw Gavaskar, not out 71, in Bengal's overnight second innings score of 220 for 4, duly reached his century this morning before being sixth out for 154 after a stay of 386 minutes and inclusive of 17 hits to the fence.
Bengal, who were content to play out for a draw after having conceded a 73-run first innings lead to the home team, were then dismissed for 382, 100 minutes into the second session, leaving Mumbai the improbable task of scoring 310 for an outright victory.
The hosts finished at 81 for one in 34 overs before the match was called off after the eighth of 15 mandatory overs in the last hour of play.
Apart from Gavaskar's century, in which he faced 259 balls, the other highlight of the Bengal second innings was the seven-wicket haul by Mumbai captain and left-arm spinner Nilesh Kulkarni.
The lanky slow bowler claimed 7 for 114 after a marathon stint of 49 overs. His career-best is still 7 for 60 claimed against Andhra in the last season.
Kulkarni's figures were only the third best by a Mumbai bowler against Bengal, following former all rounder Manohar Hardikar's 8 for 39 in Kolkata half a century ago and Ramesh Powar's 7 for 85 last season, also at Kolkata.
Mumbai gained two points from the tie to take their tally to six from three while Bengal's tally stayed at 7 from the same number of matches.