Heat forward Kelly Olynyk makes the game-winning basket against the Wizards in Washington’s season opener Thursday night at Capital One Arena. (Geoff Burke/USA Today Sports)

This wasn’t the plan.

Over the summer, the Washington Wizards designed a team ready to play small. Through a month of training camp, the team drilled the importance of rebounding when forwards convert to centers and guards and wings overtake five-man groups. The Wizards planned for their vulnerabilities underneath the glass by stressing team rebounding, then botched the strategy on opening night in a 113-112 loss to the Miami Heat.

Miami outworked the small-ball Wizards under the boards, spoiling the home opener at Capital One Arena. Miami pulled down 22 offensive rebounds, the biggest coming from Kelly Olynyk in the final seconds.

Wizards fans remember Olynyk as the villain in green from a long-deceased rivalry. Olynyk, a former Boston Celtic who was once flattened by Kelly Oubre Jr. and memorably torched the Wizards in Game 7 of a 2017 playoff series, heard boos cascading toward him every time he touched the ball.

Olynyk gave Washington fans new reason to jeer him when he grabbed a miss from Dwyane Wade and put in the game-winning layup with 0.2 seconds remaining.

“That’s been talked about for a while now, a year or so,” Coach Scott Brooks said. “When we play small, and we did tonight with all the foul trouble that we were in, we got to man up and put bodies on bodies and rebound the basketball. Like the last play of the game, same thing, gave up an offensive rebound. John [Wall] did an incredible job at contesting one of the game’s great players in Wade. But we gave up the offensive rebound.”

Olynyk finished with only four rebounds, but as a team Miami pulled down 55 compared with the Wizards’ 40.

“Anytime you lose by a shot like that at the end, an offensive rebound, the way we’ve been getting killed all game,” Wall said, “it’s very devastating.”

Although Wall produced 26 points — the fourth 20-plus opening night game of his career — to go with nine assists, his missed 26-footer before Miami’s last possession highlighted Washington’s off shooting night from the three-point arc (7 for 26).

Still, Wall carried the team through the first half with 18 points and played aggressive defense with three blocks. While Wall flexed early, Bradley Beal only could find a rhythm late.

Beal could not escape the whistle and played out of rhythm because of long stretches on the bench. When Beal picked up his fifth foul early in the final quarter, he jogged to a baseline seat and plopped down. Frustrated, Beal slapped the stanchion before heading to the bench. Beal returned to the court with 6:44 remaining, and though he still could not connect with his jump shot — 2 for 7 from beyond the arc — he made a driving three-point play and caught a lob pass from Wall for the point guard’s ninth assist.

Beal finished with 20 points on 7-for-16 shooting, and Jeff Green came off the bench for 17 points.

While the NBA opener is supposed to set the table for the new season, the Wizards could not let a few old habits fade away.

There were odd technical fouls when Wall rushed into a slight tussle for the ball between his teammate and Hassan Whiteside but instead pushed Derrick Jones Jr. And there was Oubre, chirping at Whiteside after a ferocious putback dunk.

The trend of Otto Porter Jr. playing a passive role in the offense continued. Porter did not score a point until the 2:49 mark of the second quarter. He didn’t earn his first field goal — needing two cracks at a layup near the rim — until almost a minute remained in the quarter. He also did not take a single shot from beyond the arc despite Brooks noting during the preseason that Porter has a green light to shoot just about at all times. Thursday was the first time since Oct. 27, 2016, in which Porter did not attempt a three-pointer.

Also, the Wizards’ custom of losing games in which they are expected to win continued from last season.

The Heat had three inactive players and played in the second night of a back-to-back, yet Miami manhandled the Wizards where it mattered.

For Washington, Dwight Howard highlighted the inactive list, missing the game while working his way back into form after an injury.

Howard’s highlight was waving to the crowd during player introductions. Then he exited for the locker room to receive treatment. As an inactive player, Howard could sit on the team’s sideline only if he wore a sport coat. But Howard didn’t bring a suit to the arena — he assumed he would be making his Wizards debut. The decision not to play came later, before Brooks addressed reporters almost two hours before tipoff.

Ian Mahinmi resumed his role in the starting lineup but played less than 12 minutes because of foul trouble, finishing with three points and four fouls. His backup, Jason Smith, followed the trend and sat the majority of the second half with four personals. Without traditional big men, the Wizards pivoted to their small-ball lineup with either Markieff Morris or Green at the five spot.

Washington closed the game with both forwards on the floor. Morris checked Whiteside but showed the versatility of the lineup while switching on to guard Wade during a late defensive possession. However, by going small, the lineup loses rebounding prowess, which came back to bite the Wizards at the worst possible time.

“We got to get five guys crash. They got a bunch of great bounces tonight, and they do a great job of crashing the board every time. Guys hustle. They’ve got a bunch of scrappy guys,” Morris said. “They got over on us tonight.”