In their Eastern Conference semi-final series with the Cleveland Cavaliers, one of the biggest decisions for the Toronto Raptors was who was going to guard LeBron James.

Having failed to successfully nullify the league's best player for the last two seasons, they needed another strategy to try and contain him.

Many had tried and not been able to shut him down. The likes of DeMar DeRozan, Kyle Lowry, DeMarre Carroll ad P.J. Tucker all took turns in recent campaigns but to no avail.

So for this series, head coach Dwane Casey made the brave decision to give the responsibility to a rookie.

Competing in his first postseason, OG Anunoby was given the daunting task of defending arguably the greatest player of all time.

Although James racked up the points in a sweep over the Raptors, the 20-year-old can be proud of his efforts against the Cavs superstar.

LeBron was dominant in almost every game but Anunoby didn't make life easy for him as he made him earn every bucket.

The King knocked down countless ridiculous fadeaways throughout the series which, as a defender, you simply can't do anything about.

Forcing a player like James to take fadeaway jump shots and three-pointers is considered good defence as you're preventing him attacking the rim.

In that sense, Anunoby did a great job defensively. He never gave the four-time MVP much space and was always close to him when he had the ball.

Speaking after Monday night's 128-93 game four victory that sealed Cleveland's passage to the conference finals, James reserved praise for his young counterpart and predicts great things from him.

“I think he has a bright future. His future is now, actually,” James said, per The Globe and Mail.

“You look at the rookie class from this year, it’s probably the best since 2003,” he added.

The three-time champion was the number one pick in 2003 in a class that also featured Dwyane Wade, Carmelo Anthony and Chris Bosh.

The London-born Anunoby, however, went slightly under the radar in the 2017 draft as the Raptors selected him with the 23rd pick.

He suffered a torn ACL in early 2017 and this likely affected his draft stock. But Toronto was not put off by the Indiana University product and he's now looking like a solid prospect for the future.

“I think he’s just getting more confident on what his abilities are,” Raptors all-star guard Kyle Lowry said. “He’s super-athletic, super-strong. He can shoot the ball so I think those things are just going to continue to build.”

The likes of Donovan Mitchell, Lonzo Ball and Jayson Tatum have been getting much of the attention all season while he has quietly been going about his business.

Being given the confidence to guard a player like LeBron will only make him better and the Raptors have seen enough in the playoffs to know they have a talented player on their hands.

Listen HERE to episode two of the new GiveMeSport NBA podcast, featuring New York Times senior writer Marc Stein.

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