Minnesota United striker Angelo Rodriguez is questionable for Tuesday's Open Cup

Striker Angelo Rodriguez is the only Minnesota United player questionable to play in Tuesday's U.S. Open Cup final at Atlanta, his team's first chance to win a trophy in its third MLS season.

Rodriguez trained some with his teammates Sunday after he missed Thursday's 1-0 loss at Sporting Kansas City because of a hamstring issue. Midfielders Ozzie Alonso and Kevin Molino trained fully Sunday after they, too, missed the game, and both are expected to play against the defending MLS champions.

United coach Adrian Heath said Rodriguez is "probably" the only player who will be a game-day decision Tuesday.

"It's difficult, because we have to think about the big picture also," he said. "After this, we have three really important games that we're going to need everybody."

Tuesday's game is for a trophy that has been awarded since 1914 in a tournament contested within an MLS season. The forthcoming three games at LAFC and Houston and at home against Real Salt Lake are for three points each in the tight Western Conference playoff chase.

Heath's history coaching Orlando City led to Friday's announced hiring of goalkeeping coach Stewart Kerr, who will work with veteran Vito Mannone and rookie Dayne St. Clair.

Kerr, 44, played professionally in his native Scotland as well as in England, but a back injury ended his career at age 26. He has coached and developed goalkeepers since 2008, including England's John Ruddy, Brazil's Julio Cesar, Seattle's Stefan Frei and Philadelphia's Joe Bendik. He has coached MLS goalkeepers including Frei and Bendik in Toronto, Vancouver and Orlando City.

"I've worked with Stewart before; he's an outstanding goalkeeping coach," Heath said. "… I think we've got a good core group of goalkeepers, and I think he'll really enjoy working with them. J.P. will work in different areas with the club. We've got big recruitment coming up, and he'll have a big hand in that."

United doesn't play at Allianz Field again until a Sept. 7 friendly against Mexican Liga MX team C.F. Pachuca. That will give the team more time to manage what United managing partner Bill McGuire called a "water-control issue" in a sophisticated drainage and heating system that goes 10 inches below the playing surface. Players have torn up chunks of grass with their plastic spikes on softened grass early this season and again in a recent game against Orlando City.

"We've been picking at it and trying to optimize it this first year," McGuire said. "I'd say it's less than it's going to be and less than we want it to be. It's still playable, obviously, and it's still a reasonable field, frankly better than a lot of fields out there. But it's certainly not what we're going to have. We're working on it."

The next game scheduled there is the U.S. women's national team's international friendly Sept. 3 against Portugal on its "Victory Tour."

United is expected to travel approaching 500 strong — staff, a fan charter and others traveling on their own — to Atlanta for Tuesday's Open Cup final.