Minnesota United coach Adrian Heath kept his four-man back line intact Sunday for the second consecutive game, a decision that left veteran left back and team captain Francisco Calvo neither starter nor sub.

Calvo was eligible to play after he served a one-game suspension Wednesday for a red card received in Toronto the game before. But Heath chose to keep Eric Miller at Calvo’s spot, with Brent Kallman, Ike Opara and Romain Metanire as the last line of defense.

“Obviously, he’s disappointed not playing and I didn’t want any negativity about the group today,” Heath said. “He’s obviously disappointed and I thought it’d be better if we left him out altogether today.”

That new back line has delivered consecutive shutouts against two of Major League Soccer’s better teams, L.A. Galaxy and D.C. United.

Heath said it would have gone against everything he preaches defensively to change his back line Sunday.

“We’ve spoke long and hard about keeping a clean sheet,” Heath said. “I think it would have been pretty hypocritical if I’d been talking about clean sheet, clean sheet, clean sheet and then we go and change it.”

Early exit

Minnesota United star Darwin Quintero played after he fell to the field and clutched his ankle following a tackle in the 30th minute. FS1 reported he received a cortisone shot at halftime. He played six more minutes before Miguel Ibarra replaced him. Quintero walked carefully to his locker after the game.

“We don’t know,” Heath said about Quintero’s condition. “He’s in a lot of pain at the moment, so we’ll see.”

Disallowed

D.C. United forward Donovan Pines’ header goal in the 21st minute was disallowed after video review determined D.C.’s Frederic Brillant interfered with Loons goalkeeper Vito Mannone. It came moments after Mannone made a diving save on Lucas Rodriguez’s blast.

“I couldn’t jump,” Mannone said. “One guy was completely focused on me, the other one was free to make the header. The ref said straight away he was going to check it. I obviously thought it was a foul.”

Mind the grass

Players from both teams dug up pieces of Allianz’s new grass field again Sunday.

“It’s a little bit of a concern at the moment,” Heath said. “I feel for the groundsman because he has had 3 feet of snow on it for three months. It is cutting up a little bit more than we expected, so we’ll see what we can do to help him and help the grass.”

Etc.

• Mannone played a two-game Football League Cup semifinal against D.C. United star Wayne Rooney in 2014 when Rooney played for Manchester United and Mannone for Sunderland. Mannone proved himself heroic in penalty kicks at Old Trafford, sending his team to the final at Wembley Stadium. “That’s something that sticks with you,” he said. “It’s difficult to beat such a great club in such a great stadium.”

• Opara wore a protective headband for the second consecutive game after he suffered a seven-stitch gash over his eye in Toronto two games earlier. The defender said he would wear it the rest of the season without bother, if he must.