Memphis Grizzlies wing Tony Allen has been one of the most effective and versatile defenders in the NBA for several seasons, laying claim to the deserved title of "Grindfather" for his gritty team and regularly guarding and locking down the best scorers on opposing teams. Allen may not be the greatest offensive threat in the league, but he's a weapon regardless. Few teams can deploy such an accomplished defender to handle so many different kinds of players.

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While Allen's defensive talent is well established, he has never really given extended insight into his process. That's not the case anymore, because Allen sat down with Bleacher Report's Jared Zwerling for a long look at how he defends some of the best scorers in the NBA. Here's a sample:

With a player like Kevin Durant—and anybody 6'7" and up because I'm 6'4"—the best thing to do is sit on the front of his leg because he's going to try to post me and then rely on Marc Gasol, the 2013 Defensive Player of the Year, to come over and help. I know if KD catches it straight up, he's going to score, get an assist or get fouled. And KD has gotten more aggressive in his career, so I've got to make it difficult for him to catch it, especially because he's been trying to get me with that one-legged fadeaway. [...]

When I'm facing up a guy, like Kobe Bryant, I don't watch his feet; I try to give him one way to go. Through my film study, I know which way to force him based on his moves in the previous game. In one play earlier this season, I forced Kobe left to the middle, which we're not supposed to do; that's our team principle. But in the previous game when Kobe played the Clippers, he took Matt Barnes baseline and reversed dunked. So I said to myself, You're not going to Matt Barnes me, and I forced him left and into a turnover (below). [...]

But one guy I haven't figured all the way out yet is James Harden. He's pretty crafty. I'm not impressed with his ball-handling, but his finishing skills are scary. Even though he's lefty, if he goes right he's going to put the ball out and get the foul. It's kind of tough because you don't want to get a foul called. And once you get your first or second foul, you kind of ease up. [...]

When I'm guarding somebody, I don't play percentages. I hate analytics and Synergy because a lot of times I've heard a coach say, "This guy can't shoot, he can't do this, he can't do that." And he's the one that ends up hurting us. During the game, I'm making sure to look up at the scoreboard, but I'm not looking at my points; I'm looking at my guy's points. That just keeps me motivated.

I just study the opponent in my own way, one game at time. I have short-term memory; on to the next game. I only have one long-lasting memory: my big block against Pau Gasol in Game 5 of the 2010 Finals, which we ended up winning.

We've seen these sorts of inside looks before from fantastic defenders like Andre Iguodala (something of a naturally blessed intellectual) and Shane Battier (a data-driven analyst, at least according to Michael Lewis), but Allen appears to rely on intuition and his own guile. That's not especially surprising given what we see from him on an nightly basis. Nevertheless, it's interesting to see him describe how he uses those tools to his advantage, particularly in cases like the Kobe turnover where Allen may choose to go against the superficially logical decision because circumstances dictate otherwise. It's a plan based on contingency — Allen practices and prepares, but he embraces the fact that he has to defend in the moment.

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Perhaps that's why he hasn't yet figured out Harden. While the Rockets star has his tendencies and habits, he is a master of breaking players down off the dribble, which tends to involve a set of moves and feints rather than a single go-to shot or spot on the floor. To put it another way, Harden is effective on offense for many of the same reasons Allen succeeds on defense — he takes advantage of momentary lapses and opportunities with ruthlessness. If Allen hasn't figured Harden out, then it could be because Harden's tendencies are not easy to figure out from short-term study.

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