The Toronto Raptors' hopes of containing LeBron James rest primarily with their 20-year-old non-lottery rookie -- and that could actually be a good thing for Toronto.

OG Anunoby has shown flashes of being a capable defender against the King in the past, and is the logical candidate to match up against James in the Eastern Conference semifinals that kick off Tuesday night in Toronto, as the Raptors -- for the third year in a row -- attempt to get past the Cleveland Cavaliers in the playoffs.

In the regular season, Anunoby -- who tore his ACL playing for Indiana in January of 2017 and slipped to the 23rd pick of the draft as a result -- emerged as Dwane Casey's primary choice to defend James. The former Hoosier matched up against the Cavaliers' star 106 times -- almost double the next-highest amount for any other Raptor. And it's easy to see why: When Anunoby marked James, the Cavaliers scored 1.09 points per possession. That might not sound like a great defensive performance, but that scoring rate is a decent bit below the Cavaliers' season average with James on the court (1.14). And the real key is this: When any other player on the Raptors marked James, the clip the Cavaliers' offense scored at ballooned to 1.38 points per possession.

In other words: If that sample is any indication, Anunoby is the best the Raptors have.

There's also reason to believe that he actually is a solid choice to try to contain James beyond just that relatively small set of possessions against the Cavs this season. Against the entire league, Anunoby has already proved he is an elite defender against drives. In fact, opponents scored only 0.83 points per direct drive against him in the regular season, which tied for the third-lowest rate among all players who defended at least 200 drives. A direct drive is one in which the ball handler shoots, is fouled, turns the ball over or passes to a teammate who shoots after no more than one dribble.

Pretty clearly, that's a necessary component to at least slowing down James, who scored the fourth-most points per direct drive (1.19) in the league among those with at least 200 such plays, and was the most efficient among anyone with at least 500 drives.

In a small sample, Anunoby's drive defense did hold up against James, who scored 12 points on 14 direct drives against the rookie. For what it's worth, on 19 total drives, James failed to "blow by" Anunoby a single time. That relates to what seems to be the key for the young Raptor: his positioning, which forces opponents into more difficult shots.

The quantified shot quality (qSQ) of opponents in the paint who took at least three dribbles prior to their shot and were closest to Anunoby this season was 45.6. In other words, given the location of those shot attempts, what type of shots they were and the positions and movements of both the shooters and Anunoby, those shots had an expected effective field goal rate of 45.6 percent, which translates to the 98th percentile for defenders.

The numbers suggest Anunoby may be susceptible to collapsing toward the basket a tad quickly, given that his quality of shots allowed on pull-up jumpers ranks only in the 31st percentile.

Last year, in the Cavs' sweep of the Raptors, Toronto mostly placed current Rocket PJ Tucker on James. Cleveland scored just over 1.1 points per possession when that was the case. Tucker was a capable drives defender last season (0.92 points allowed per direct drive), but not to the same level that Anunoby is now. Two years ago current Nets player DeMarre Carroll was James' primary defender and the Cavaliers' offense was explosive against Toronto when that was true.

Just as impressive as Anunoby's drive defense against James this season is the drop-off in James' assist production. He averaged 12.1 assists per 100 possessions this season ... but managed just 4.7 when Anunoby was matched up with him. Again, it's not a huge sample, but for the Raptors, it's a promising sign that their rookie presumably used his length to defend passing lanes and limit James' ability to find teammates for assist opportunities.

Of course, James isn't one of the world's greatest basketball players based on just one or two offensive skills. And that's where the outlook gets a little dicey for the Raptors. If James decides to post Anunoby up, the rookie could be in trouble, because he has allowed 1.00 point per direct post-up this season, which is below league average.

But the most concerning part about Anunoby's defense is a fairly large caveat to the praise we've heaped upon him already. Though the rookie forces opponents to take lower-quality shots, he isn't quite as skilled at disrupting the shooter. Even after accounting for the skills of each shooter, opponents have shot slightly better than the quality of their shots would suggest over Anunoby (to the tune of 1.7 percentage points of EFG rate). Based on those traits, it will be interesting to see if James makes a concerted effort to attempt more post-ups and shots from distance.

While his drawbacks indicate Anunoby isn't an elite defender, he is a good one. Toronto kicks off the conference semifinals as a heavy favorite (88 percent chance to win the series) over Cleveland, according to the Basketball Power Index -- which has been down on the Cavaliers all season. It would be hard to imagine the Raptors would have that good a chance had they gone in a different direction with the 23rd pick of the 2017 draft.

Data provided by Second Spectrum. All statistics are from the regular season only.

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