VANCOUVER, British Columbia (AP) — The Vancouver Whitecaps and Seattle Sounders combined for just one shot on target in a 0-0 draw to open their Western Conference semifinal on Sunday night.

Vancouver, which missed the MLS playoffs last season, and Seattle, the 2016 MLS Cup winner, kept things tight with neither team willing to take many risks.

The return leg is Thursday at Seattle.

The Whitecaps, who finished third in the West standings, were coming off the club's first-ever playoff victory — a 5-0 demolition of the San Jose Earthquakes in Wednesday's single-elimination knockout round.

The Sounders, meanwhile, won three of their last four in the regular season, including a 3-0 home win over Vancouver to grab second spot in the conference and secure a bye to the semis.

The Sounders were without leading scorer Clint Dempsey, who was suspended, while fellow striker Jordan Morris (hamstring) was among Seattle's walking wounded.

Sounders defender Chad Marshall rose to head the match's one and only shot on target in the 48th minute, but goalkeeper Stefan Marinovic was there to make a comfortable save.

The Portland Timbers visit the Houston Dynamo in the first leg of the other Western Conference semifinal on Monday.