AMSTERDAM – Young MK Dons goalkeeper Cody Cropper will miss four to six weeks after undergoing knee surgery this week.

The timing of the injury puts his availability for October's CONCACAF Olympic qualifying tournament in serious doubt. Cropper worked the first half of the US Under-23s' 1-0 friendly loss to England on Friday. Zack Steffen worked the second half of both that match and the US's 2-0 win against Qatar on Tuesday, with Ethan Horvath starting the win over the Middle Eastern nation.

Since moving over from Southampton this summer, Cropper has opened his pro account with a pair of Capital One Cup victories for Championship club MK Dons, including a penalty shootout win over Cardiff City late last month.