KANSAS CITY, Mo. — As they head into their CONCACAF Champions League opener, Sporting Kansas City's roster seems to get more and more depleted every day.

Fullback Kevin Ellis is the latest scratch for Wednesday's match at Nicaraguan side Real Estelí (10 pm ET, Fox Soccer), manager Peter Vermes told reporters after Monday's training session. Ellis, who has played on both sides this season, has a hip injury and is being evaluated this week.

"We're getting thinner by the moment," said Vermes, who estimated he had a pool of maybe 19 players from which to draw Wednesday's 18.

Midfielder Graham Zusi, who pulled up with a sore right quad in last week's MLS All-Star Game, heads the list of unavailable players. Midfielder Paulo Nagamura is still working back from an ankle sprain, and left back Josh Gardner is out with a hamstring strain.

"We've got some other guys with some nicks and little issues here and there," Vermes said. "Then we've got some other guys who maybe need a little rest because they've played so much, so it's just a lot of different things. I was hoping to be in a different place with all the guys, but we'll have to manage it."

Vermes did not say who he planned to start against Real Estelí, but in the past has said rookie midfielder Mikey Lopez and longtime No. 2 goalkeeper Eric Kronberg (above) were candidates for Sporting's XI in CCL play.

"It's what I'm hoping for," said Kronberg, who has made two US Open Cup starts this season. "That's kind of been the plan all along. So of course I'm looking forward to it, but I have no idea what it's going to be like because I haven't been through it. Hopefully we can go down there and get a good result, so we can bring the team back home and move ahead in our group."

Lopez, whose only appearance came in an Open Cup start against Des Moines on May 26, has played in both Central and South America as a member of the US Under-20 national team.

"It should definitely help me be used to the speed of play and how they play, and how their cheekiness and cleverness is — going down easily and stuff like that," he said. "It's always best to play as the visiting team in a different country, because everyone's going to hate you and that inspires you and motivates you to play a lot better."

Whatever Sporting's result in Nicaragua, they won't have much time to recuperate from the trip — which includes a three-hour bus ride from the airport to the match and another on the way out. The team will fly back on Wednesday night and arrive Thursday morning, with a home league match against New England on Saturday — part of a crowded August that sees Sporting play five times in the league and twice in CCL.

"This is an important month for us, so with all the issues we've got going on with the team, we've got lots to manage here in a short period of time," Vermes said. "We've got all these guys injured at the moment. That's really hurting us. But we'll deal with it. We'll figure it out."

Steve Brisendine covers Sporting Kansas City for MLSsoccer.com.