Updated

Nikolay Davydenko retired in the first set, sending Vasek Pospisil through to the semifinals at the Rogers Cup on Friday.

Pospisil had a 3-0 lead when his opponent informed the chair umpire he could not continue. Pospisil will next play the winner of the afternoon quarter-final between Canadian Milos Raonic Latvian Ernests Gulbis.

After the match, Davydenko said he has bronchitis. The Russian has been ranked as high as No. 3 in the world but currently holds the No. 47 position.

Pospisil, a wild-card entry, upset American John Isner in the opening round and then topped Czech veteran Radek Stepanek. The 71st-ranked Pospisil followed that up with a stunner on Thursday when he knocked off fifth-seeded Tomas Berdych of the Czech Republic. It was the Canadian's first win over a top-10 player.