TORONTO — Having had to make do without captain Michael Bradley because of Copa America, Toronto FC now finds itself without another key player.

The MLS club said Tuesday that goalkeeper Clint Irwin will be out for six weeks with a quadriceps strain.

The 27-year-old left Saturday's 3-2 loss in Orlando in the 70th minute after injuring his leg on a routine goal kick. Alex Bono came on to make his MLS debut as his replacement.

Bradley, who has missed Toronto's last six games while on international duty with the U.S., is finished with Copa America but remains a question-mark. A club official said Tuesday he was back in Toronto for medical evaluation of a knee injury.

"Hopefully (he'll be back) pretty soon," coach Greg Vanney told a news conference later in Vancouver. "I don't think it's a significant thing by any means."

The U.S. captain was substituted in the 79th minute of a 1-0 loss to Colombia in the third-place Copa America game Saturday.

Playing every minute, Irwin had been at the heart of a retooled Toronto defence this season. Acquired from Colorado in the off-season, he is tied for the league lead with six shutouts and has eight clean sheets in all competitions.

Toronto (5-6-4) which tied Chicago and New York City FC in yielding a league-worst 58 goals last season, has conceded just 18 goals in 15 games this season and rank sixth in the league giving up 1.20 goals a game.

Irwin is a reliable, low-maintenance goalkeeper who has been the glue in Toronto defence along with veteran centre back Drew Moor, another off-season-acquisition.

In Irwin's absence, Toronto has the 22-year-old Bono and 21-year-old Quillan Roberts as options in goal. Both are touted prospects but have all of 20 minutes MLS experience between them.

Bono, a first-round pick in the 2015 MLS SuperDraft who has already earned a call-up to a U.S. national team camp, made his MLS debut Saturday. Roberts, who has won one cap for Canada at the senior level, has played for the first team in friendlies but has yet to appear in an MLS match.

The two 'keepers have seen regular USL action for Toronto FC II.

Toronto, holding a 1-0 lead, visits Vancouver on Wednesday night for the second leg of the Amway Canadian Championship final.

Toronto is still waiting the return of star striker Jozy Altidore, who has been out since mid-May with a hamstring injury.

Ironically, Irwin's injury came in Orlando, whose starting' keeper is former Toronto No. 1 Joe Bendik. On Saturday, Toronto hosts Seattle and another former TFC goalkeeper in Stefan Frei.

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