TORONTO -- At film session the day following their late-night flight home from Orlando early Monday morning, Toronto Raptors coach Nick Nurse finished by screening one final clip -- a clip that, in his eyes, was most representative of the team's growth over the series.

A possession from the Raptors' Game 4 victory, the clip began with Kyle Lowry dribbling left courtesy of a screen from Serge Ibaka. As Lowry attacks the paint, he kicks the ball to a wide-open Norman Powell behind the arc on the weak side -- only Terrence Ross leaps in the air and snatches the pass with his left hand.

The Magic are off to the races, but if you freeze the frame, something interesting reveals itself. Outside of Ross, who is pushing the ball up the floor, the three figures running with the greatest resolve and stride are Lowry, Ibaka and Fred VanVleet, who is leading the pack. By the time Ross crosses half court, it's a 1-on-4 break, with Powell sprinting into view, followed by Kawhi Leonard.

"We were up 19 with 5:46 to go, but we didn't give them anything," Nurse says. "This one clip showed how our mindset has changed. Five guys flying in, and they had to pull it out. I said, 'There's no better way to impose your will.' [Ross] steals it and is thinking dunk, and all of the sudden he has nothing."

The Raptors have won four straight playoff games, their longest playoff win streak in franchise history. Nathaniel S. Butler/NBAE via Getty Images

After dropping the opening game in the series, the Raptors were angry at their defensive effort, a rage that fueled a four-game rally -- capped by the clincher in Game 5 on Tuesday, a 115-96 win -- in which they decimated the Orlando Magic with their defense. Toronto moves on to face Philadelphia in the conference semifinals.

Though the Magic came into the postseason as a below-average offensive squad, the Raptors assembled a defensive clinic in their first-round series win. The lockdown of the 7-seed highlighted a stark reality that occasionally got lost in a season dominated by discussion of Leonard's load-management program, his pending free agency, the maturation of Pascal Siakam and the midseason acquisition of Marc Gasol.

The Raptors are loaded defensively.

The team sports two former defensive players of the year in Leonard and Gasol, a three-time first-team NBA All-Defense winner in Ibaka, an All-Defense second-teamer in Danny Green, a point guard in Lowry who consistently ranks near the top of the league defensively at his position in the most advanced defensive metrics (his backup VanVleet rates highly, too), and Siakam, who might have been better than all of them this season.

Even the best personnel needs to deploy quality schemes, because NBA offenses are a handful. What emerged in the series win over Orlando is a unit that operates on well-honed principles bolstered by basketball intelligence. It starts at the top of the floor where those assigned to guard the ball really guard the ball. Even when it was Michael Carter-Williams, a guy against whom most NBA defenders will happily run under screens on the pick-and-roll, Raptors defenders fought over him. If regular-season coverage calls are any indication, don't expect them to slough off Ben Simmons when they encounter the Sixers this weekend -- he'll likely be engaged at the point of attack.

After being torched by D.J. Augustin in Game 1, the Raptors shut down the Magic's pick-and-roll game with brute force. After that loss, Toronto yielded a microscopic 0.71 points per direct pick -- best in the playoff field. They built a high wall to deter Augustin, with the big man playing up, smothering the action. The Raptors will mix up coverages, with no fear of having guards like Lowry switching into the post, happy to entertain mismatch basketball if the opposing offense wants to disrupt its flow.

"After Game 1, we kind of understood what kind of level defensively we need to play," Gasol said. "In every game, I think we improved in different areas -- and we kept improving. That's a great sign."

Even though they feature strong, versatile one-on-one defenders all over the floor, the Raptors help willingly, and with great alacrity. This looks like a vintage-era San Antonio outfit that's decisive about the help it offers, and timely and precise in its recovery. Leonard has long been the best in the game at announcing his omnipresence with authority on defense, and at the sound of the postseason starting gun, he reverted to his exquisite form. He has a seamless ability to both account for his man on the wing, and provide, as a helper, the key disruption of a possession -- or vice versa.

Willing help defense can often yield available 3-pointers to opponents, and the Magic took a ton of them in the five-game series. Fortunately for Toronto, frequency was not matched with accuracy. Against a Sixers team that ranked eighth in 3-point percentage this season, the Raptors might need to be more selective in their help. JJ Redick will run his defender ragged, and Joel Embiid won't succumb to being pushed out of the post in the manner Nikola Vucevic was by Gasol.

If there are threats, the Raptors will attend to them -- blitzing Terrence Ross on the catch or double-teaming Vucevic if Gasol isn't defending the post. Rotations aren't ideal, but there's so much confidence in the collective smarts of the defense that these are risks Toronto will incur. Such is the luxury of a veteran-laded roster with no weak links.

After his final news conference, Clifford likened the Raptors' defense to a skilled NFL secondary that can account both for individual matchups and open space, citing Leonard and Gasol in particular. Gasol noted that it was unlikely Vucevic had ever been doubled on cuts: "I'm sure that he didn't like that as much." Indeed, Toronto presents an unlikeable brand of defense if you're a big man trying to carve out space to operate. Embiid is more creative than Vucevic, but no more appreciative to defenders cramping his style.

The Raptors have endured as much upheaval over the past year as any team in the NBA playoff field -- the departure of a franchise star, a new head coach, three new starters and a fourth with a skill set that's unrecognizable from a year ago. Along the way, that cataclysmic change has produced anxiety, some hurt feelings, massive expectations and, as it has settled, a defense that should concern any opposing offense that doesn't have multiple options and contingencies.

At their best, past Raptors teams overachieved defensively. This one doesn't need to.