Five months ago, Danilo Acosta would have been among the players trickling off the practice field in ones and twos, instructed to make it a light training session after starting two days before.

Not this season. Acosta, instead, stayed behind with the other non-starters Monday for a longer session after sitting on the bench for Real Salt Lake’s 5-1 loss to LAFC on Saturday.

Acosta, who won a starting spot at the end of last season and received his first senior national team call-up in January, has yet to start in 2018, suggesting a disconnect between the coaching staff’s expectations of the homegrown player and its evaluation of his performance this season whether physically, or more likely, mentally.

“Is it unexpected that a young player has ups and downs?” RSL general manager Craig Waibel told The Tribune. “No. It’s unexpected if the organization thinks players don’t have ups and downs. ... But we have to figure out how to speed up to get him back where he was.“

RSL coach Mike Petke declined to comment on Acosta’s situation Monday, saying, “It’s not about individuals, for the most part. Maybe that’s a question for Danny.”

It seems there has been an accumulation of little things that have eroded Acosta’s standing with Petke. The Tribune has learned a report back from the USMNT camp raised concerns about Acosta’s attitude. During one preseason training session in Tucson, Acosta talked to reporters before the team had finished stretching and didn’t respond to Petke’s summons until he had finished the interview. In RSL’s season opener, a giveaway by Acosta led to an RSL own goal in a 1-1 tie with FC Dallas.

Back in January, Petke expressed 2018 hopes for the 20-year-old left back with ”all the talent in the world,” the day after the USMNT announced its 30-man roster for camp that included Acosta.

Petke said Acosta had “made tremendous strides” when it came to his mentality and setting high aspirations for himself.

“That’s why he’s been my No. 1 guy on the left over the important part of the last season,” Petke said in January, “and that’s why he’s got his call-up. But there can’t be any dip in form.”

After returning to RSL, Acosta started in the team’s first two preseason matches before losing his spot to veteran Demar Phillips.

RED BULLS AT REAL SALT LAKE

When • 7 p.m. Saturday

TV • KMYU

“He has done really well in preseason and all that,” Acosta said about Phillips, “and I feel like he deserves it. But my mentality has to be I’ve got to keep working hard because it’s a long season. This is just the beginning.”

Acosta and Chris Wingert competed for time at left back last year after Phillips suffered a hamstring injury in July. Acosta made the position his by September, starting seven of RSL’s last eight matches of the season. While RSL signed reinforcements at right back and center back, the club’s only offseason move at left back was re-signing Phillips.

Acosta entered preseason the presumed starter although to Phillips’ credit, the 34-year-old Jamaican defender returned healthy and motivated. After evaluating the two players for more than a month in preseason, Petke named Phillips the starter in the season opener at FC Dallas on March 3.

“From a club perspective,” Waibel said, “the expectation is that a player’s going to come back at his age better than the way they left. And if that happened he would be starting.”

Acosta’s first regular-season appearance didn’t help his case. Petke subbed Acosta on in the 77th minute after Phillips cramped up and had to leave the game. A giveaway by Acosta nine minutes later led to an own goal as Marcelo Silva attempted to clear a cross with Dallas forward Cristian Colmán making a back-post run behind him.

Beyond that mental mistake, Acosta’s play didn’t highlight the explosive speed and improved consistency that helped win him the starting spot last season.

After playing for Petke for almost a year, however, Acosta said everyone on the team knows what they need to do to earn playing time.

“You just have to work hard,” Acosta said, “and then give your 100 percent no matter what.”

DANILO ACOSTA

Position • Defender

Birthplace • San Pedro Sula, Honduras

Hometown • Sandy

A breakout 2017 season • Acosta made his MLS debut April 8 against Vancouver after spending most of the 2016 season with the Monarchs. He went on to log two assists in 17 matches last season.