Vasek Pospisil upset favoured compatriot Milos Raonic 7–6, 3–6, 6–7, 3–6 in the first round of the US Open on hard court on 3 September 2020. Despite entering as the clear betting favourite at 1.17 odds, Raonic could not convert his advantage, with Pospisil mounting a comeback to claim the match in four sets through competitive tiebreak contests in the opening two sets. The Canadian's upset victory represents a significant result in their head-to-head record and provides momentum heading into the second round.