In the end, Casey became a victim of his own creation. After securing the No. 1 seed in the East, the stakes rose last spring. Boston was weakened by a season-ending injury to Kyrie Irving, while LeBron and the Cavaliers hiccuped their way through the season and nearly lost in the first round to the plucky Pacers. This was Toronto’s chance. Until it wasn’t.

Casey was doomed after a pair of events in the semifinals with Cleveland: He didn’t double LeBron on the superstar’s running one-hander at the Game 3 buzzer (which drew a stern postgame lecture from Ujiri to Casey) and didn’t have his team prepared in Game 4, when the Raptors were swept away, losing by 35 unacceptable points.

The Cavs ousted the Raptors in the 2018 playoffs.

In that series, DeRozan came up small and was benched in the fourth quarter of Game 3. Initially, the only proposed change was Casey’s job, which Ujiri called “the hardest decision I’ve ever had to make.” But when the relationship between Leonard and the Spurs couldn’t be patched and San Antonio put him on the market weeks later, DeRozan was a goner, too.

DeRozan took that move personally, vowing to never speak to Ujiri again. But this was business, pure and simple, and to put it bluntly, Leonard is the better player. The guess is almost every GM in basketball would’ve pulled the trigger, even without any future assurances from Leonard.

“When you get a chance to get a top five player, which doesn’t come very often, you have to jump on it,” Ujiri said. “We’ve given a chance to this team. We’ve tried to build it as much we can. This opportunity came in front of us and we had to jump on it.”

He’s correct in this sense: Players with Leonard’s talent rarely become available. They’re known as “distressed assets,” meaning, an otherwise terrific player whose baggage creates an abrupt change of scenery. For a historical reference, see Jason Kidd from Phoenix (domestic incident) to New Jersey; Shaquille O’Neal from the Lakers (contract demands, Kobe Bryant fallout) to Miami; Dennis Rodman from San Antonio (assorted oddball behavior) to Chicago, etc.

Who will ultimately come out the winner in the Kawhi Leonard trade?

In each of the above cases and in others, the arriving player either produced a Finals run (or title) or, at the least, changed the culture of his new team. Leonard has the two-way talent to make positive waves in Toronto. Just five years ago, he shut down LeBron, won a title and was named Finals MVP. Two years ago, before his injury-interrupted season, he was the Kia MVP runner-up after he improved his scoring. And he has every incentive to deliver in 2018-19, with the promise of a big contract beckoning and a chance to repair his image (if he cares, which is debatable) caused by his perceived disloyalty to the Spurs.

This is another to add to the list: Carmelo Anthony from the Nuggets (disenchantment) to the Knicks. Curiously, Ujiri was the triggerman on that deal from the Denver side, and it was the move that launched his career. In this particular case, Ujiri worked from a disadvantage; everyone in the league knew he had to move 'Melo, who was approaching free agency the next summer and wanted to play in New York. Instead of panicking, Ujiri, then new to the job of general manager, waited until the right deal, then struck, getting assets from the Knicks, enough to help the Nuggets turn the page without suffering on the floor.

That helped Ujiri land his dream job in Toronto and also enhanced his rep as one of the best team-builders in basketball.

With Leonard, Ujiri has a superstar, someone who can change a game and fit well with Lowry. Otherwise, the Raptors are relatively the same quality team that has lived in the attic of the East and should reside there once again this season.

How many games will the Raptors win in 2018-19?

“He’s super healthy and working like heck,” said Nurse of Leonard. “A special player.”

Nurse’s background reads like a coaching gypsy. Five years ago he was in the D-League (now G League) where he won two titles, and before that, he spent 11 years coaching in the British Basketball League. When the Raptors hired him as an assistant, he had no prior NBA experience in any capacity. He was in charge of the offense under Casey.

“This is my first head coaching job in the NBA,” he said. “If you look at the alternatives, if you look at the seven or eight coaching changes, most of the others are 30, 35-win teams that are a ways away from the playoffs … we’re firmly entrenched, and rightly so, in the Eastern Conference championship talk. It’s great. We’re where we should be. We’re going to go for it.”

Lowry was grumpy for months after the Leonard-DeRozan trade because he and DeRozan were tight on and off the court. But that was just a stubborn show of loyalty to his friend, and besides, time heals. Lowry knows a relationship with Leonard is crucial to the season and that process has begun.

“We have to be on the same page,” Lowry said this preseason, “and we will be on the same page.”

The Raptors have plenty of roster variations to throw at foes this season.

Of course, the elephant in the room is Leonard’s contract status. Unless there’s a sudden change in strategy, Leonard won’t sign an extension this season and will weigh his options this summer. Should he bolt for a sunnier situation -- the hometown Lakers or Clippers, perhaps -- Ujiri will be forced to address the next phase of the Raptors. And in that scenario, he could press restart, trade Lowry (whose contract expires in the summer of 2020) and create from scratch.

But that’s a season away, and in the meantime, Ujiri has a concept to show to his newest and most important acquisition.

“I think there’s a lot to sell here,” Ujiri said. “Our team. Our culture. Our city. Our ownership. We have everything here except a championship in my humble opinion.”

Are the retooled Raptors any closer to a championship now than last spring, when LeBron destroyed their dreams? The Celtics will have a say in that, maybe the Sixers as well. Ujiri knows championship windows don’t stay open very long for 95 percent of the league (the Warriors being the exception). You must do what it takes to keep the breeze blowing in, even if tough decisions involve a pair of the most important people in club history.

“I have to do everything in this organization to get us to a championship level,” Ujiri said. “There’s also a human side of this business and that’s the part I really struggle with the most … the human part doesn’t make it easy at all.

“Our team (was) just not at that level. We have to do something different, even if it wasn’t this. I could have done anything I wanted. At some point we have to do something different."

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Veteran NBA writer Shaun Powell has worked for newspapers and other publications for more than 25 years. You can e-mail him here, find his archive here and follow him on Twitter.

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