ORLANDO, Fla. — One of the most dramatic moments of the 2012 MLS preseason unfolded on Friday night in the Vancouver Whitecaps' 3-0 win over the Montreal Impact on the opening day of the Disney Pro Soccer Classic.

Near the close of the first half, Vancouver veteran midfielder John Thorrington crouched down to one knee and held his face. With no other players within five yards of him, it was clear from the resignation on his expression that something had gone wrong after weeks of newspaper articles featuring his return to full fitness from nagging groin, calf and quad injuries last year.

The Whitecaps informed MLSsoccer.com that Friday's issue, which forced Thorrington out of the match, was a quad strain, and it will be reevaluated on Saturday. Gershon Koffie, who was a regular starter in 2011, replaced Thorrington for the rest of Friday's match and would project as a possible replacement.

"These types of things are part of the game, but it's a big blow for us," Whitecaps captain Jay DeMerit told MLSsoccer.com after the match. "He's one of our key guys, one of our foundation guys. But the good thing is that muscle injuries are something that can be healed in time and healed quickly. So hopefully it's not too serious and he can get back up there."

Vancouver was also forced to sub out another starter in the first half when Davide Chiumiento similarly bent over in some discomfort and was subbed out in the 24th minute. According to the Whitecaps, the midfield playmaker is day-to-day with back spasms.

At the conclusion of Thursday's practice, Chiumiento was spotted receiving what the club previously called routine treatment targeting his back on a trainer's table placed at the practice field.

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