Those of you who have read prior versions of Prada's Pictures will remember the concept of acting vs. reacting that I've harped on a number of times. In essence: a defense is successful when it shuts off what the offense wants to do before the play begins, forcing it to react and try something different. When a defense becomes the actor rather than the reactor, it is in business.

All season, the Memphis Grizzlies' defense was the league's best at being the actor. Led by Marc Gasol's unbelievable defensive intelligence, the Grizzlies overplayed teams to the point where they couldn't do anything they wanted to do offensively. When you force any team out of its first option, it is going to struggle.

But in Game 1 of the Western Conference Finals, the San Antonio Spurs turned the actor vs. reactor concept on its head. How? By disguising their plays.

In particular, their pick and roll plays were beautifully hidden. The Spurs performed a nice trick on a number of them, pretending to set the screen one way, then either declining it or having the screener shift at the last minute to go the other way. Memphis' big men were caught out of position because they were positioned to shut off what they thought was the initial play, allowing the Spurs to get into the lane and get easy shots.

For example, watch what Boris Diaw does on this play. The initial setup makes it seem like he is going to spring Tony Parker to get middle.

Parker is dribbling with his left hand and Diaw appears to be coming in at an angle to get Parker on the move. The Grizzlies' defense is aligned to stop that. Zach Randolph is hanging back to Parker's left, and Tayshaun Prince has taken a few steps off Kawhi Leonard to further plug dribble penetration to the middle.

But Diaw isn't screening to spring Parker to go left. Instead, he darts ever so quickly to Parker's right before the Grizzlies' defense can react.

This is a brilliant maneuver because Randolph is prepared for the play to go middle. Once he sees Diaw switching sides, he overreacts, running to get in position instead of sliding his feet. Notice how his feet are crossed here, which prevents him from being on balance to contain Parker.

Parker only needs to shed Jerryd Bayless, his man, to take advantage of the Grizzlies' confusion. This proves to be an easy task because Bayless too is out of position. Once Parker gets free, he hits the off-balanced Randolph with a crossover dribble and accelerates to the rim.

Here's the play in real time.





Here's another example of Diaw disguising his screen to confuse Randolph and the Grizzlies. This time, Diaw comes parallel to Parker on a high pick and roll. Randolph, meanwhile, overplays to Parker's left, while Bayless is defending Parker straight up.

Diaw again sneaks to Parker's right, and the Grizzlies don't react quickly enough. Bayless doesn't get over the top to force Parker left, and Randolph doesn't rotate over to get in Parker's way.

This allows Parker to again get to the rim for a layup.

Here's that play in real time.





The Spurs also often went the opposite way of a ball screen during the game. Here, Danny Green sees the Grizzlies overplaying for him to come off a Tim Duncan screen.

Mike Conley and Marc Gasol are anticipating that Green will go to his right and have already prepared to stop that. They are trying to act to force the Spurs to react. But Green instead makes a quick move to his left and gets all the way to the basket for a layup.

Gasol is not in position to help Conley because he took himself out of the play by guessing Green would go middle. Green therefore gets all the way to the basket before Gasol can cut him off.

Here's that play in real time.





And then, there's the matter of Matt Bonner. The Spurs' sharp-shooter hit four threes and confused Memphis all game. A lot of Bonner's success was due to unacceptable breakdowns, most of which included Darrell Arthur. But the Spurs were also smart at varying the way he set screens to open up opportunities for himself and others.

Here, he performs a Diaw-like maneuver, switching sides on the pick and roll until he creates an opening for Gary Neal. At first, Bonner sets up for Neal to go left...

Then, he switches for Neal to go right...





Finally, once he sees Randolph overplaying to Neal's right, Bonner lightly brushes Conley to free Neal to go left again. This time, Neal makes the move and gets into the second level of Memphis' defense.

Here's the play in real time.





In this example, Bonner pretends to join Tiago Splitter on a double drag screen in transition for Manu Ginobili. The Grizzlies don't have any help defenders stationed to Ginobili's right because they are assuming he will drive left into the double screen.

Ginobili does go left as the Grizzlies expect, but as it turns out, Bonner is not joining the screen. He actually ends up running through the play and spotting up on the right side, where no Grizzlies defender is located.

The Grizzlies therefore have nobody to step out on Bonner on the right wing. The Spurs' sharp-shooter will nail this shot eight times out of 10 if you give it to him.

Here's that play in real time.





Finally, the Spurs, including Bonner, actually set traditional screens every so often. On this play, the Grizzlies are defending as if they expect Bonner to switch sides again on his screen. They are anticipating the Spurs' counter, as weird as that sounds.

But instead of changing the play for Parker to go left, Bonner stays where he is and sets a solid screen. Randolph is caught way out of position.

This allows Parker to get into the lane, and once he does that, he draws so much attention that multiple Spurs shooters are open. San Antonio only needs to rotate the ball to get a good look.

Here's that play in real time.





The Spurs' style of play is a huge adjustment for Memphis. The Grizzlies have just defeated two teams (Clippers, Thunder) that have very little misdirection in their offense. The play you think they're running is usually the play they actually run. While the Spurs don't have individual stars like Chris Paul, Blake Griffin or Kevin Durant, they run an offense that is anything but predictable. Memphis can get away with cheating on the offensive sets of the Thunder and Clippers. They can't get away with cheating against the Spurs.

In other words: being the "actor" on defense means something completely different against a team like San Antonio. Rather than overplay pick and rolls, the Grizzlies may need to consider defending them straight up. Otherwise, San Antonio will counter its defense to death.

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