John Alvbage endured a boot to the leg in Sunday's match and will be out one to three weeks while the gash heals.

Patrick McLain hasn't practiced with the team all week with a concussion.

So that leaves Major League Soccer veteran Bobby Shuttleworth as possibly Minnesota United FC's lone goalkeeper standing as the team heads to Colorado Rapids for an 8 p.m. match Saturday.

Shuttleworth came on for the injured Alvbage in the dying minutes of the 6-1 loss to Atlanta, and he will start in goal this weekend, despite just coming back from a "bit of a knee issue."

"I haven't had a ton of time to play with these guys, seeing as I just got here and then was dealing with an injury," Shuttleworth said, adding his knee is pretty much pain-free now. "Just trying to help them out as much as possible and try to get us in the right spots and me pick up good positions."

However, that leaves an empty seat on the bench for an emergency backup keeper, should McLain not clear concussion protocol in the next four days, coach Adrian Heath said at practice Tuesday.

Short of sending out goalkeeping coach Marius Rovde in a pinch, this would qualify under MLS' "extreme hardship" rule, where teams can add players to the roster if there are fewer than two available goalkeepers.

Sporting director Manny Lagos said how the team would go about finding another goalkeeper is still being sorted out with the league, and he would know more about the situation Wednesday. MLS usually has a pool of goalkeepers that can be allocated to teams in emergency situations. A loan could also be a possibility.

Alvbage and McLain are two of four United players currently injured. Defender Joe Greenspan also has a concussion from last week and hasn't cleared protocol yet. Midfielder Bernardo Anor is still on the disabled list with a nerve problem in his leg.