India A resumed at the overnight score of 23 for three, and Gill, starting at 2, reached his century just at the stroke of lunch. His overnight partner Shahbaz Nadeem fell for 13, after resuming on five, early in the day.
Captain Vihari (118 not out) then joined Gill in the middle and the two resurrected the Indian innings after the top-order collapse. The duo notched up an unbeaten 315-run stand for the fifth wicket before India A declared on 365 for 4 soon after Gill scored his double ton.
At stumps, West Indies A were 37 for no loss, chasing a massive 373 for victory on the final day of the four-fay match.
Gill bounced back strong from his a first-ball duck in the first innings and his unbeaten knock of 204 was laced with 19 fours and two sixes with a strike rate of 82.25.
While Vihari, who had earlier bailed out India in the first innings with a half century, continued in the same vein, hitting 10 boundaries and a maximum.
Earlier, West Indies A bowled out India A for a meagre 201 in the first innings on the opening day of the match before folding for 194 in their first essay.
Gill’s impressive knock comes days after he failed to find a spot in India’s tour of the West Indies. India have already pocketed the series by winning the first two games of the series.
India A: 201 and 365/4d in 90 overs (Shubman Gill 204 not out, Hanuma Vihari 118 not out, Chemar K Holder 2/88)
West Indies A: 194 and 37/0 in 15 overs (Jeremy Solozano 20 batting)