Andre Blake is still out injured, and is in talks over his next Union contract

Union star goalkeeper Andre Blake remains sidelined with the knee injury he suffered last weekend and is out for Saturday’s game at D.C. United (7:30 p.m., Apple TV, free).

Backup Oliver Semmle will start again, and with No. 3 netminder Holden Trent still recovering from surgery on a broken hand, reserve-team starter Andrew Rick will be called up to the first team for the fifth time this year.

“Andre still has pain in the knee … he’s not quite ready yet,” manager Jim Curtin said in his weekly news conference Friday. “So we’ll be smart with him. Doesn’t make sense to risk possibly injuring it worse.”

That puts Rick over the limit of four times a year that a reserve player can be called up in hardship circumstances. As a result, the Union have to sign him to a first-team contract. That hasn’t been formally announced yet, but you can expect it.

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Rick was going to get a first-team deal sooner or later, probably next year. But the 18-year-old’s move up now means the Union must use a roster spot on a fourth goalkeeper for the rest of this season, which isn’t ideal.

“Nothing’s official, and there’s still paperwork going on,” Curtin said, “but as [I’ve] said before, Andrew Rick’s going to be a Union first-team player sooner rather than later, call-ups aside.”

Fortunately, the team has the space on its roster right now to sign Rick and not run out of room for moves this summer. Because so many players are loaned out, there are two open spots on the senior part of the squad and three spots on the supplemental part (though one should be saved for David Vazquez).

Curtin also addressed the clouds gathering over Blake’s contract status. He’s in his last guaranteed year and would like a new deal, and Curtin would like him to get it.

“I think everybody involved wants Andre to be part of the Philadelphia Union — certainly the head coach wants that as well,” Curtin said. “Our relationship is great. It’s open; it’s honest. He’s been the best goalkeeper in this league for quite some time and is a big reason why we’ve had success over the last several years.”

» READ MORE: What we know (and don’t know) as MLS reveals more details on Union players’ contracts

He also signaled that talks are underway. That might be another clue about Blake’s recent vague complaint on Instagram.

“I’m always confident that things will sort themselves out in a positive way,” Curtin said. “But yeah, those things are ongoing now, and that’s between them and a little bit behind the scenes.”

Along with addressing Blake’s contract status, Curtin also had to put out a fire with José Andrés Martínez.

The stalwart defensive midfielder aired some grievances on social media with a post in his native Spanish at halftime of Wednesday’s loss to Seattle, when he was subbed off: “If the one at home doesn’t screw you, the one who visits will screw you,” with a hashtag that translates to “they are all [expletives]” and a few emojis.

Martínez deleted the post a few hours later, but fans captured screenshots before then — and raised alarm not just over the words, but over him getting on his phone during a game.

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“He’s not happy with a lot of things,” Curtin said.

He signaled he knew what Martínez is upset about, but didn’t go into detail.

“I have a pretty good idea of things and have my finger on the pulse with all these guys,” Curtin continued. “It’s like a family: We all love each other, but we also have passion about our sport and have disagreements just like any work environment. … I don’t want guys that are happy when they get subbed out at halftime.”

He does, though, want his players to keep their complaints private.

“Is it the smartest thing to do? I think things should stay always in-house and in the locker room,” he said. “But it happens, and these are human beings, and they have emotions, and sometimes it’s OK to express those emotions.”

The best way for the Union to snap out of all of this, of course, would be to win a game for the first time since April 6. And it sure would help Semmle if his teammates step up defensively, which they haven’t done lately. The Union have just two shutouts in 13 games this year and none since March 30.

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“There is no denying that the ball’s hit the back of the net far too many times,” Curtin said. “Fluky plays [and] penalty kicks can happen, but our box defending needs to be more strong and better. The difference between making a hard tackle and staying on your feet in certain instances, and making it predictable for Oliver, is also something that we need to do a better job of.”

Centerbacks Jakob Glesnes and Jack Elliott have regressed, and while a midfield with Jack McGlynn and Quinn Sullivan can do some great creating, there’s a sacrifice on the other end. Leon Flach’s return would help balance that out, even if it means taking McGlynn or Sullivan off the field. Right now, it feels like that’s a sacrifice the Union need to make.

“I don’t want to win games 6-5,” Curtin said, and if you’re new to the Union, know that he’s always been this way. “As entertaining as that is for the fans, I just know that’s not sustainable in our league, with what we’re about, and going end-to-end with some of these teams, with some of the attacking pieces they have.”

As for Semmle not being as good as Blake? Of course he isn’t. That’s why he’s a backup. And almost no one else in Major League Soccer — and well beyond on the continent — is as good as the longtime No. 1 for the Union and Jamaica’s national team.

The rest of the Union’s lineup might change, but that fact won’t.

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