The Union will play a lot of backups in their Open Cup opener at Orlando

Union manager Jim Curtin doesn’t usually like to say much about his starting lineups for upcoming games. But with a Tuesday game at Orlando City FC in the U.S. Open Cup preceding Saturday’s league home game against the rival New York Red Bulls, Curtin decided he might as well tell the truth this time.

So he went ahead and revealed more than half of his starting lineup for the Union’s first game in the competition this year (7 p.m., ESPN+).

Matt Freese, Stuart Findlay, Matt Real, Olivier Mbaizo, Jack McGlynn, Quinn Sullivan, and Paxten Aaronson are all set to start, Curtin said Monday in a phone call with reporters.

“It’s a competition that I really love and respect, and I think that we’re going to put a good, strong team on the field,” said Curtin, who won two Open Cups as a player in Chicago. “We’ll still have guys that all are capable of winning games for us on the field, so it’s not like it’s a huge drop-off. And we think we have a deep team, so this is a chance where that depth gets tested, and you’ll get to see some guys showcase themselves for more minutes.”

That Curtin could make the claim is a testament to the depth of his roster, and the quality of his team’s youth academy products. All of the players Curtin mentioned have done enough to deserve a shot but have been kept off the field by a starting lineup that has the Union atop the Eastern Conference at 5-1-4.

“It’s been difficult to get the minutes this season as starters because the first group has performed so well,” Curtin said. “We’ve been beaten once all season, so there hasn’t been a real reason to change too much or tinker with the starting lineup.”

» READ MORE: Top teams in Major League Soccer, Union and LAFC, battle to 2-2 draw

That’s not the only reason why Curtin hasn’t had to tinker. The Union haven’t played a midweek game yet this year, so everyone’s been able to get full rest after a game.

Now the Union are about to play two midweek games in succession, and there will be a third if they beat Orlando. After this week’s round of 32, the round of 16 will take place on May 24 and 25, between the Union’s road games at Portland and New England. The draw will be held Thursday, and by tournament rules the Union will be drawn against a team from the eastern part of the country.

(Orlando will probably rotate its lineup some, too, as it’s between league road games at Montreal and Toronto.)

Of the seven players Curtin named, the biggest spotlights will be on Aaronson, Real, and Mbaizo.

Aaronson has played just 41 minutes in MLS over six games this year, mainly because Dániel Gazdag has been outstanding. Aaronson has played much more with the Union’s reserve team, making three starts and registering a goal and an assist. This will be an opportunity for him to take the reins in a start for the first time since last November.

Real has played in two MLS games this year, both last-minute cameos as a defensive substitute. He’s been doing well in practice, and if he does well in this game scouts will notice — though not just because of him. While the Union have fielded trade offers for Real, the bigger deal is the summer offers for Kai Wagner that are sure to come.

“Matt’s been at his very best so far this season in training, [and] he’s done a good job in the Union II games,” Curtin said. “This will be an opportunity now with the first team to get minutes, and he deserves those minutes.”

Mbaizo hasn’t played for the Union since the second game of the year, when he came off the bench after losing the starting right back job to Nathan Harriel. He likely won’t get it back any time soon because Harriel has continued to be terrific, including in Saturday’s 2-2 tie at LAFC that ended Sunday morning back home. But Mbaizo deserves a shot to play some, so he can remind the club and the Cameroon national team of his talents.

» READ MORE: The Union’s Olivier Mbaizo dreams of the World Cup after being part of Cameroon’s qualification

Whoever else ends up starting or coming off the bench, there are two outfield players we know we won’t see: Mikael Uhre and José Andrés Martínez. Uhre has stayed in Philadelphia to shake off tightness in the same quad muscle where an injury caused him to miss two games earlier this year; and Martínez is dealing with a knee issue that flared up Saturday night and caused him to be subbed out.

Curtin said Martínez had surgery on the knee last year, and still has some flare-ups of pain. Martínez was to get a scan on Monday.

“He mentioned fairly early [on Saturday] that he didn’t feel great,” Curtin said. “He then pushed himself and kept going on the field. I don’t think it was any one play, it’s just been kind of wear and tear, which is scary for sure.”