BOSTON — Immanuel Quickley walked into the interview room in Houston and talked about he’s so cautious he’s showering with his mask on. It didn’t work.

Quickley become the fifth Knick to enter COVID-19 safety protocols, the club announced. And there could be more coming as all the players tested positive since returning last weekend from Toronto.

The Knicks also have two broadcasters from their traveling party in protocols — Walt Frazier and Rebecca Haarlow.

After scoring 24 points in Houston on Thursday, Quickley was summoned into the small interview room late Thursday at Houston’s Toyota Center and spent several moments contemplating whether to take off his mask.

Quickley eventually removed his face covering.

“It’s definitely crazy right now,’’ Quickley said before learning of the diagnosis. “I’ve been showering with my mask on, which is crazy itself. I just try to keep it on, and hopefully, it will keep me safe. I try to be as cautious as I can. I keep my mask on all the time. I haven’t taken my mask off like this.’’

The Knicks were already minus four players because of COVID-19 (RJ Barrett, Quentin Grimes, Obi Toppin and Kevin Knox). None of the five will be available when the Knicks face Boston on Saturday at TD Garden.

If Derrick Rose, listed as questionable with a sprained ankle, isn’t available, Tom Thibodeau will have no choice but to play the banished point guard Kemba Walker against his former team, the Celtics.

The Knicks are hardly out of the woods.

A road victory Thursday in Houston, inspired by rookie point guard Miles McBride, over the depleted and rebuilding Rockets certainly has not taken the Knicks out of the woods.

They still are battling a COVID-19 outbreak, shorthanded, on edge, still below .500, in lottery position and not buoyed by a trove of believers.

“That’s why the East is the East — it got even more competitive,’’ said veteran Taj Gibson, who came up clutch in Houston in filling in at power forward. “People didn’t believe in us last year, and we did the opposite. This year is no different.

“We understand the bandwagon is empty. We understand a lot of people [are] counting us out. We believe in ourselves, believe in the group and can’t listen to what everybody is saying.’’

As relieved as Thibodeau was with the win, he mentioned the defense still needs to be better if they are to beat Boston. The Rockets were missing three starters but shot 50 percent highlighted by an array of emphatic dunks.

The Celtics entered Friday situated in eighth place, while the Knicks (13-16) are in 12th. Nobody expected this free fall after their fourth-place 41-31 renaissance season, when they broke a seven-season playoff drought.

“I’m a little surprised, but I don’t think it’s over,’’ Quickley said before his diagnosis. “The league is pretty good right now, but we feel we’re good as well. We just got to stick with it and, hopefully, can turn it around. Through the tough times, I think we’ve stuck together pretty well, though. It’s a long season.’’

There’s been some concern about the in-house leadership. Neither Julius Randle or Rose are considered vocal rah-rah types. Gibson is just that, but he’s out of the rotation when the team is at full strength. Walker no longer plays, and newcomer Evan Fournier hasn’t established himself.

“I think we do [have enough leaders],’’ Gibson said. “It just comes down to guys believing in one another. That’s part of my job, to keep building guys up. Leaders don’t just come over night.

“You’re going to be thrown so many different curveballs. You’re going to lose. Look at the East — everybody’s going through a funk. Everybody is going to have off nights. But we’ve just got to stay together.’’