TORONTO — Dwane Casey remembers Jonas Valanciunas’ first season in the NBA well. The Lithuanian centre was just 20-years-old; raw and unpolished. He’d never faced quick, high-intensity offences like the ones that were now flying at him on a nightly basis in the NBA.

"He’d say, ‘coach, they’re coming at me real fast!’ And it was Kemba Walker or Kyrie Irving who was coming at him. I don’t even think Jonas knew these guys’ names yet. But they were coming at him fast," the Toronto Raptors head coach says. "But now, it doesn’t faze Jonas at all. He’s used to that speed. He can gauge it. He moves his feet. And he does a much better job."

That was evident Tuesday night, as Valanciunas played active, engaged defence throughout his 28 minutes on the floor in a 96-90 Raptors win over the Charlotte Hornets. In fact, both Valanciunas and his back-up, Bismack Biyombo, were the two key cogs in shutting down a Hornets team that counts on offensive contributions from it’s versatile big men, Cody Zeller and Al Jefferson.

"Their bigs can really shoot, so we had an important job to just be up on them all the time," Valanciunas said. "You can’t let them shoot wide open shots, because they can make them. So we had to take that away."

In all, Valanciunas and Biyombo held Jefferson and Zeller to a combined 14 points on 6-of-15 shooting, and outrebounded the Hornets duo 19-17. And if you take away Zeller’s fourth quarter—when he scored six of his nine points as the Raptors defence slipped for the first time on the night and allowed the Hornets to claw their way back into the game—the work the Raptors’ frontcourt did looks even more impressive.

"They’re a good challenge. Because Jefferson is great on the low post, so we’ve got to take his pump fakes away, and limit his penetration towards the basket," Valanciunas said. "And Zeller is just so active. He’s everywhere. He’s going to the boards, he can shoot. They’re such different players, so it’s a big job."

The Raptors duo prepared for that job in different ways. Valanciunas values his work with the Raptors coaching staff, and spends plenty of time discussing the steps he has to take to stop pick-and-rolls, and the distance he can keep in one-on-one situations.

Biyombo, meanwhile, is a video junkie. He studies film of his opponent’s recent games to pick up tendencies and see what kind of sets they run in different situations.

"I always have an iPad around me to watch the other team’s last few games and see their different plays. I study each and every team night in and night out. I know exactly what I’m going up against every night," Biyombo says. "So, tonight, there were a lot of plays that I was just ahead of. I knew what was coming and I was able to anticipate it. It’s worked for us."

Casey thinks being around a player like Biyombo, who’s renowned for being a deterrent at the rim, has helped push Valanciunas to improve his own work under the bucket.

Every time Biyombo takes the floor, a loud, impactful defensive moment isn’t far away. Valanciunas will likely never be that kind of player, but he has been contributing more resilient rim-protecting plays as the season has worn on.

There were a number of them Tuesday night, like late in the second quarter when Valanciunas defended a pick-and-roll perfectly and finished with a strong block of Frank Kaminsky’s lay-up. Or a couple minutes later, when Valanciunas stretched out to the perimeter to adjust a Courtney Lee attempt that missed the rim entirely.

Then, late in the fourth as the Hornets were fighting their way back into the game, Valanciunas came out from under the basket to swat away a Kemba Walker attempt, sending the guard crashing to the floor. That’s the same Kemba Walker who Casey remembers giving Valanciunas fits in his rookie season.

"I think he’s learned from Biz, understanding speed and distance, how far he can get up on pick and rolls, how far he can get back. It’s a very fine line," Casey says. "He really has improved in reading the speed of the game."

Who knows how much Valanciunas’ improvement has had to do with having Biyombo around and how much it’s due to his natural evolution as a player. After all, he’s still only 23.

But what we do know is that as the Raptors enter the playoffs, teams will be hunting for weaknesses in their defence, trying to find anything they can exploit to force the Raptors into uncomfortable positions. If Valanciunas can guard active big men like he did Tuesday night, it gives the opposition one less weak point to attack.

"He’s put a lot of energy and effort into improving," Biyombo says. "And that’s good because we’re going to need everybody in this locker room in the playoffs. We’re going to need everybody at their best for us to accomplish what we desire to accomplish. It’s going to be exciting to see him continue to grow."