Bradley Beal goes up to shoot during the Wizards’ loss to the Portland Trail Blazers on Saturday night. (Geoff Burke/USA Today Sports)

Before tip-off Saturday night, John Wall showed up on the Washington Wizards sideline with the assistance of crutches. The franchise point guard and one of the fastest men in the NBA needed a prop just to walk after receiving platelet-rich plasma and viscosupplementation injections to try to reduce the inflammation in his ailing left knee.

Wall remained on the sideline during the Wizards’ 108-105 loss to the Portland Trail Blazers, sitting next to the coaches during the action then standing on the periphery for every huddle.

With Wall out, Washington relied on a two-man council of Bradley Beal and Otto Porter Jr. that eventually resulted in a team-wide collapse.

The Wizards’ tendency to blow big leads manifested itself once again as they led by 17 points in the fourth quarter before Portland went on a run. With 21 seconds remaining, Portland guard C.J McCollum drilled a 20-foot jump shot over Porter to give the Blazers a 106-105 lead. Although Beal had a chance to help Washington retake the lead with an open midrange look, his shot ricocheted off the rim and the Blazers collected the rebound before Pat Connaughton made two free throws. Given another opportunity, Beal could not connect with an off-balance three at the buzzer.

“I wish we could explain it,” Beal said about the late-game letdown. “We’ve got to stay aggressive.

“We thought the game was over. The game is never over. They kept hitting. They were knocking down shots, getting stops… They closed it out. We didn’t.”

The road to defeat was paved with a bad foul (Markieff Morris committed a flagrant against Portland’s Jusuf Nurkic, which led to a four-point possession and trimmed the Wizards’ lead to 105-102 with 1:30 remaining), plenty of missed shots (the Wizards did not score in the final 2:30 of the game) and egregious defense (McCollum scored seven of his team’s final nine points, including the three-pointer following Nurkic’s missed second flagrant free throw).

“That second half, particularly in that fourth quarter,” Coach Scott Brooks said, “we just couldn’t get stops.”

Through all of this, Wall, the Wizards’ most important player, was reduced to doling out special handshakes to teammates and raising the roof to acknowledge Tim Frazier’s surprising slam dunk in the third quarter. As strange as it appeared to see the electrifying Wall this limited, such will be the routine for the near future.

Wall, who averages 20.3 points and 9.2 assists, is projected to miss about two weeks. According to that timeline, Wall could miss seven games including Saturday’s loss and possibly return Dec. 9 when the Wizards (10-9) will be in Los Angeles to face the Clippers.

As Brooks addressed the Wizards’ first major setback of the season before the matchup with Portland (12-8), he revealed that Wall underwent an MRI exam and the results showed no structural damage. The test proved to be a sliver of good news, but the reality of the day remained: Washington will be without its all-star point guard for a while.

“It’s not the ideal situation. You lose one of your best players for a couple weeks, but it’s next-man mentality,” Brooks said. “Our guys, I feel very confident they’re going to come back, play and compete by committee.

While Portland’s backcourt duo of Damian Lillard (29) and McCollum (26) combined for 55 points Saturday, Beal and Porter combined for 50 on 19-for-39 shooting. Porter scored 18 of his 24 points in the second half and pulled down 10 rebounds, the most among his teammates. Beal flashed his playmaking skills by sprinkling in a game-high seven assists to go along with his 26 points. Beal’s sharing freed up Frazier, who will replace Wall as the starting point guard, to score a season-high 11 points. Frazier also threw down the breakaway two-handed flush that got Wall to stand up and celebrate — part of Washington’s  25 points off 16 turnovers.

Even so, the team’s offensive punch couldn’t prevent a poor home loss in front of an announced crowd of 18,092 at Capital One Arena.

“It came down to defensive stops, because we couldn’t score in that last six or seven minutes,” Brooks said. “We made some critical mistakes.”

Although Wall initially made his knee a public topic after Nov. 11, the team is now placing the source of inflammation at Nov. 7, when he made “knee-to-knee contact” during a play in the game against the Dallas Mavericks. Wall consulted with the Wizards’ head physician, Wiemi Douoguih, as well as Dr. Richard D. Parker at the Cleveland Clinic Marymount. In May 2016, Parker performed the procedure to remove calcific deposits in Wall’s left patella tendon after Wall had played the previous season in pain. Brooks said the current inflammation is unrelated to the surgery from over a year ago, and doctors, the team and Wall’s representative came to an agreement that injections would be the best route for treatment.

“Gives him the best chance to calm the knee down,” Brooks said. “So hopefully after a couple of weeks, he’ll be back on the court and play the season out. He’s definitely as tough as they come. He doesn’t want to miss games, but it’s the best thing for him.”

In some instances, players have not returned so quickly after receiving the treatment — in which a doctor extracts some of the patient’s own blood and injects into the injured areas to help with healing. Last December, Wizards backup center Ian Mahinmi needed PRP injections in both knees and missed six weeks. In June, Kelly Oubre Jr. underwent the treatment and returned to workouts during the team’s early stay in Las Vegas for the NBA Summer League in July.

Also, Hornets backup guard Michael Carter-Williams needed treatments on the patella tendons in both knees in July but did not return to full practices until the regular season, according to the Charlotte Observer. Last season, Detroit Pistons guard Reggie Jackson used the injection to treat left knee tendinitis and missed the first 21 games of the season and did not return to form as he appeared in just 52 games.

Although on Saturday morning the Wizards indicated Wall’s recovery timeline as “approximately” two weeks, Brooks would later tell reporters the team can be flexible in bringing him back.

“Whenever, long as he’s ready. If it’s 17 days or it’s 12 days . . . it doesn’t really matter,” Brooks said. “As long as he’s ready and he’s ready to play and the doctors and John’s representative, myself, our staff and [General Manager] Ernie [Grunfeld], we’re all in agreement he’s ready. He’ll be ready.”

Brooks used the entirety of his 13-minute pregame media availability fielding questions about Wall. Last year, the Wizards rarely had to address injuries. As Washington ascended to fourth in the Eastern Conference, the team dodged significant injuries. At that time, among the team’s core players Markieff Morris had missed the most time in sitting out six games. This season, however, Morris missed the first seven games while recovering from surgery to repair his abdominal wall. And now, an even more painful sight: Wall in warmup gear for an extended period of time.

Wall controls the Wizards’ offense and fast breaks, and even while he has struggled to find his shot (.435 shooting percentage through 16 games played), Washington still thrived with a 109.7 offensive rating, the fifth best in the league. Without Wall, the Wizards collected 20 assists on 41 field goals Saturday night, coming close to their season average of 22.2 assists. After the game, Wall walked off on his own power, without crutches, but maybe his teammates could’ve used the assistance.

“It’s two weeks. It’s not the entire season,” Brooks said. “It’s two weeks and hopefully we can manage it.”

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