So Pospisil’s journey ends in the first round, and he is the one who reached the final in this tournament last year.
He lost the 68th in the world in three sets 7-5, 6-7 (8/10), 3-6 to 112th seed Gerasimov.
Pospisil led most of the match but couldn’t hold up in the third set.
Gerasimov will also face young Italian Yannick Sener, who defeated Pospisil in the final last year, in the round of 16.
The 31-year-old Canadian will be taking part in the Indian Wells Championships from October 7-17, after more than a year of absence.
Still on the men’s side, four more matches were played on Tuesday for this first round.
Local candidate Dimitar Kuzmanov won his match against Italian Lorenzo Mossetti 6-7 (4/7), 7-6 (7/3), 6-3.
Serbian Laslo Djere defeated Spaniard Pedro Martinez in two sets 7-6 (7/5), 6-3.
Australian John Millman, seeded in the tournament, easily beat Sweden’s Mikael Ymir in two sets 6-2, 6-4.
Finally, the American Marcos Giron advanced to the round of 16 after he finished the series of Spaniard Jaume Munnar in three sets 6-7 (2/7), 6-1, 6-4.
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