On a big Wednesday of play, former champions Roger Federer and Rafael Nadal open action in Canada. Federer, a 2-time winner, will face Canadian Peter Polansky first match on center while 3-time champ Nadal collides with Borna Coric in the early evening.
Former finalist Milos Raonic is on against Adrian Mannarino and 2016 runner-up Kei Nishikori clashes with Gael Monfils in maybe the best match of the day.
Juan Martin del Potro returns to face 18-year-old Canadian Denis Shapovalov who saved four matchpoints in a win today over Rogerio Dutra Silva. And Washington winner Alexander Zverev begins play against 2-time Canadian finalist Richard Gasquet.
On Tuesday, third-seeded Dominic Thiem was ousted by Diego Schwartzman 4-6, 7-6(7), 7-5. Thiem, who was down a set and a break, led the Argentine by 5-2 in the decider and held a total of four matchpoints, but lost the last five games of the match to the world No. 36 who collected his first career Top 10 win.
Also in the second round, American 20-year-old Jared Donaldson kept his run going beating his second straight Frenchman in Benoit Paire 6-2, 7-5.
In the first round, Jack Sock, Kevin Anderson, Sam Querrey and David Goffin were all winners. Pablo Carreno Busta ousted Karen Khachanov.
Tomas Berdych was expected to start the Center Court session against but the Czech withdrew with a rib injury. American Ernesto Escobedo took his spot and made the most of it beating Nikoloz Basilashvili 7-6(4), 6-4.
Also tomorrow, Querrey faces 2014 champion Jo-Wilfried Tsonga, Grigor Dimitrov meets Mischa Zverev and Sock faces David Ferrer.
WEDNESDAY MONTREAL SCHEDULE
COURT CENTRAL start 12:30 pm
[WC] P. Polansky (CAN) vs  R. Federer (SUI)
Not Before 2:30 pm
[WC] D. Shapovalov (CAN) vs J. del Potro (ARG)
Not Before 6:30 pm
 R. Nadal (ESP) vs B. Coric (CRO)
A. Mannarino (FRA) vs  M. Raonic (CAN)
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