Likely to join Major League Soccer next season, Minnesota United FC prepared for Wednesday’s match against Sporting Kansas City of MLS as a pass-fail exam.

The evaluation changed to letter grades after a 2-1 overtime loss. High marks for effort and intensity, the opposite for a mental lapse in the 109th minute that led to Diego Rubio’s eventual game-winning goal.

Unable to earn an upset in the fourth round of the U.S. Open Cup tournament, Minnesota, currently in the North American Soccer League, missed out on a more full validation.

“We showed we can play,” coach Carl Craig said. “We showed that we can put a very good side on the back foot. We showed that if we make rudimentary mistakes against good sides, we’ll get punished.”

The loss, played before an announced season-low attendance of 7,689 fans at the National Sports Center Stadium in Blaine, meant Minnesota could not avenge a 2-0 defeat against Sporting KC in the 2014 Open Cup.

Since then, Minnesota has stocked its roster with top-end NASL players and some MLS veterans. Sporting KC coach Peter Vermes credited the latter for Minnesota’s improvement.

“This team’s better,” Vermes said. “It’s probably more seasoned. We felt Minnesota was going to be the toughest opponent of any of the teams in the tournament at the moment. I thought they were solid in all aspects of the game. I thought we were, too.”

Benny Feilhaber put Sporting KC ahead 1-0 on a penalty kick in the 63rd minute. A successful penalty kick from Christian Ramirez in the 80th minute sent the game to overtime.

Ramirez, who works out in the offseason with Feilhaber, traded jerseys with him after the match.

“He said, ‘What an effort, what an atmosphere,’ ” Ramirez said. “He said we’ve got something special going. Coming from a guy like him, that means a lot.”

Minnesota, the highest-scoring NASL team with 16 goals in 10 spring season matches, could not score outside of a penalty kick. Ramirez missed on a chance in the first overtime session when sliding defender Ike Opara kicked the ball away.

Feilhaber later assisted on Rubio’s game-winner, slipping a ball past a momentarily frozen Loons backline.

“We switched off for half a second and it cost us,” captain Justin Davis said. “But I think we showed that we can compete with those teams. We were right there with them.”

Neither team was at full strength. Bernardo Anor, on loan from Sporting KC, missed the match because of a broken ankle. Sporting KC’s Matt Besler and Graham Zusi are playing with the United States in Copa America.

“It’s frustrating to go out like that, knowing we were inches away a couple times,” Ramirez said. “But it’s encouraging, especially against a side like Sporting, to play as well as we played.”

The clubs also needed extra time in the 2009 Open Cup, when the then-Kansas City Wizards beat the then-Minnesota Thunder on penalty kicks.