Watch how the Thunder defense led OKC's comeback win over Warriors in game 1

Well, that was exciting! Against a historically great offense in the Golden State Warriors, the Thunder defense thrived, ending with a DRtg of 97.6 while grabbing 12 steals and 6 blocks. The defense was one of the defining reasons why OKC was able to pull off the upset on the road to steal home court advantage.

Although the game was generally a success on the defensiveend, there were some concerning things in addition to the encouraging. So let's take a look at both, with the bad coming first.

The Bad

Lazy Switching

Part of the defensive plan the Thunder are employing is to switch on lots of screens. This works for the guards and wings, but it is incredibly risky to switch 1-4 or 1-5. Too often, especially in the first half, OKC switched a big onto one of the splash brothers. Kanter, in particular, was continually picked on, as he didn't have the foot speed to contest shots and cut off drives. I don't entirely blame him for that, though, as his teammates were putting him in bad spots.

This looks like the defense the Oklahoma Sooners run where everything gets switched at the top of the arc. Westbrook actually does a good job of fighting through everything to stay with Stephen Curry. Foye bites on Klay Thompson's head fake toward the rim, putting him too far behind the play to recover. Because KD switched off Livingston, this leaves Adams and Ibaka to guard Bogut and Klay. Adams does well to funnel Klay to Serge, but he reacts too slowly, ending with an open layup. With Klay's shooting ability, this is a tough guard for Adams, who has shown himself capable of defending guards in space occasionally, but will have difficulty stretching his defense out to where Klay likes to shoot.

Russ switches this way too easily. I don't know if calling switches is our bigs' responsibility or the guards', but putting Kanter on Curry this far from the rim is a bad idea, especially with Curry having forward motion. If Kanter tries to close out here, Curry would easily blow past him. Granted, that would be a better option than giving up the 3, as Kanter had Roberson and Ibaka both sagging off to help on the drive. But still, Russ easily could get over this screen, and OKC can get away with leaving Green open for a second or two here.

Just 30 seconds later, Golden State tries running the same play. Kanter is cognizant of the fact he was just beaten and fights to keep up with Curry. He does relatively well, but because he is slower, he ends up just screening Westbrook away from defending. Golden State lucked out on this horrific shot attempt by Curry, because they easily could have had a 2 on 1 inside with Roberson guarding both Livingston and Green.

I don't know what Russ is doing here, except perhaps thinking too much. He seems to be guessing that Curry is going to curl off the screen, meaning Serge is better placed to pick him up. However, by stopping inside, he allows Barnes to instead screen Serge, meaning that no one is left to contest Curry. These are the types of switches that are absolutely pointless.

Transition Defense

In the first half, OKC was getting beaten in transition over and over again. 10 turnovers were the primary reason, but Golden State was getting out off of missed shots and made shots, which was inexcusable. In the second half, OKC was getting to the free throw line and making more shots, which slowed the game down considerably. In fact, the pace dropped from 111 to 98.5 from the first to the second half. This limited the easy looks for GSW. Something else that affected the pace in the second half was offensive rebounding. Once OKC started pounding the glass, Golden State was forced to rebound with all 5 players, meaning they couldn't leak out for the breaks.

Here, the defense takes far too long to get set, and Roberson gets wiped out by a (moving) Bogut screen. Normally, Adams plays up on this and stops the ball handler, but because he hadn't found his man yet, he gets to Klay to late, giving up an open mid-range shot. This was just a mental mistake, but these types of shots allowed Klay to get hot early.

Again, OKC players all have their backs to Golden State, allowing Barnes to catch Serge off balance. In general, this isn't a bad shot if you're the defense, but it was another case of not quite being quick enough to set up to defend in the half court.

Again, they run out so fast that our defense isn't able to set up and defend. Russ has to help Adams stop ball, KD is way too out of control to defend Curry, and this is basically a 3 point layup.

Dion needs to do a better job of stopping the ball here. He doesn't slow Klay down at all, forcing the help from Kanter. Kanter is too slow to close out on this 3 ball, giving up an open look. To be entirely honest, I'm okay with Barnes shooting 3s, but I'd rather settle in to defend in the half court.

I truly believe OKC can defend Golden State with their half court defense. Obviously, the Warriors are going to put up points, but it seems as if many of their runs come from playing helter-skelter offense that catches the defense unprepared. The key to this is simple: don't turn the ball over and get back on defense.

The Good

Disruptive Hands

OKC was able to generate fast break opportunities as well. Whether it was a sloppy game by Golden State or just great defense by OKC, Golden State finished with 14 turnovers. Westbrook had 7 steals on his own and spent most of the game jumping passing lanes and making well-timed jabs at the ball. Key blocks also helped shift momentum and preventing easy looks at the rim.

This play goes back to one of my keys to defending Golden State: use help to force Curry to pass. Adams plays Curry on that inside hip while KD shades to his right and Russ floats on his left. Ezeli cuts toward the rim, but KD is sitting right in the passing lane for the easy steal and fast break.

This is a great possession for the OKC defense. Russ stays with Curry off the pass, then switches onto Barnes. The entire rest of the play, Serge bumps and bothers Curry to keep the ball out of his hands. Klay is supposed to get the ball, but Roberson locks into him and doesn't allow an inch of space. When Klay down-screens for Durant, Roberson switches off. Green wants to kick out to Klay, but Durant is still there, so Green is forced to throw a cross court pass to Barnes. Russ doesn't give Barnes space and ends up poking away his dribble.

If we can make Barnes be the play-maker like this, our defense is going to have a lot of success. This possession was the ideal was to defend Golden State in the half court.

OKC seemed to know Golden State's plays on a lot of possessions. Green makes a lazy pass to Curry, and Russ was waiting to pick it off. He missed on this type of steal attempt once as well (leading to a wide open Curry three), but being able to jump those passing lanes is going to eventually force Golden State to shift their offense a few feet further from the basket.

If  you look at the defensive preview I wrote, I showed a play just like this that Golden State ran against Boston. Dion hounds Curry on that inside hip, funneling him to Kanter at about 10 feet. The other defenders find passing lanes to sit in, forcing Curry to attempt a tough wrap-around pass in the paint. Ezeli can't handle the pass, and Westbrook is fouled before he can initiate the fast break.

This play came right after Green got a block on the other end. Klay beats the defense down court, but Serge gets one of his patented chase-down blocks. This was in the middle of a Golden State run, and these are the kinds of plays that could have made the arena erupt. Instead, Serge was able to quiet the crowd.

OKC forced Klay into a shot from the dead zone on his shooting chart, and the shot came up short. An unfortunate bounce put the ball right back in his hands, though, with another look from that range. Adams somehow gets an arm up and just swats the ball away to prevent the easy look.

Klay does a pretty good job of bumping Roberson off to get a path to the rim. Roberson recovers really well to swat the ball right out of the air to Serge. This play resulted in a layup for Roberson on the other end, making it a 4 point swing.

4th Quarter Shut-Down

In the 4th quarter, the Thunder held the Warriors to 14 points on 26-10-50 shooting splits. Golden State never seemed to find any footing offensively. Some of it was rushed shots by Golden State, but OKC also did a good job forcing players to make plays where they weren't comfortable.

On this play, Dion goes under a screen on Klay, which is dangerous. He is able to close out, though, and gets a hand in his face on the shot. This is one of those rushed shots that Golden State started throwing up. If it goes in, it's a good look, but since it doesn't, we can call it like it is: settling for bad shots.

If Shaun Livingston posting up Kanter is the best source of offense Golden State can generate in the 4th, this is going to be a short series. The real mismatch is Speights on Foye, but because Adams and KD float inside, that option is taken away. If you think OKC has spacing issues, look at the OKC defense here. 4 guys (everyone not guarding a splash brother) are standing in the paint.

This play comes off an offensive rebound. Kanter is forced to guard Curry, and he presses up to prevent a 3. Durant shades off of Green to stop the drive, forcing Curry to make the pass. Green knows he isn't taking KD to the rim, but he decides to shoot a contested 3 rather than exploit the Curry-Kanter mismatch. This is horrible offense.

The initial defense here isn't great. Serge gets matched onto Klay somehow, and lets him by to the rim. Watch what happens with the defense, though. Waiters ignores Barnes to prevent the swing pass to Curry, and since Klay sort of meanders to the same corner, both of their best offensive players are taken out of the play. Barnes has an open look, but seeing as he is missing 75% of his 3s this postseason, I think OKC will give up this shot.

I realize that Green won this matchup a few times last night, but I will take Adams 1v1 on any forward or center in this league. Green gets a step, but Adams contests from behind, forcing Green to attempt a reverse while out of control. As expected, it spills out, and Golden State has no one in position to rebound.

This is Golden State's last attempt, and Waiters defends it perfectly. They try to get him behind the play in the scrum of screens, but he stays with it to force the turnaround 3. The rebounding is also disciplined, with three Thunder players converging to secure it.

Overall, the defensive effort in Game 1 was good enough to carry the team to a win, but I believe it could be even better. The second half showed the ceiling of what this team can do on that end of the floor, and that is the level of effort that needs to be given the rest of this series.