HOUSTON -- Focusing on James Harden’s 45-point scoring barrage against the Boston Celtics is an easy starting point when it comes to discussing Houston’s 127-113 win over the Celtics.

But a deeper dive into this game reveals that as impressive as Harden was scoring the ball, it was Houston’s physicality that ultimately proved to be Boston’s undoing.

Houston was physical on the glass, evident by a decisive 54-38 rebounding advantage which helped fuel dominant 18-8 advantage in second-chance points.

The Rockets were physical with their drives to the rim, resulting in 35 free throw attempts with Harden taking 17 of them.

And they were physical in terms of bodying up the Celtics with their defense.

Celtics head coach Brad Stevens certainly gave Harden his props for a big scoring game.

But it was Houston’s physicality that more than anything else, was never matched by the Celtics (20-14).

“It was unacceptable,” Boston’s Al Horford told reporters regarding Houston’s rebounding dominance. “They were the more physical team, getting those rebounds. They kept hurting us all night on those second-chance opportunities, so you have to give them credit.”

Houston playing a physical brand of basketball was not a surprise to Celtics head coach Brad Stevens.

“They’re a really physical team,” Stevens said after the loss. “They probably don’t get enough credit for that.”

And that physicality that Stevens speaks of begins with Harden, a burly guard who poses a serious challenge for all comers.

Harden had 17 points in the first quarter, but was scoreless in the second.

“We tried to get up in his air space and he went on that stretch where he missed everything,” said Stevens, referring to Harden missing 11 straight after making six of his first eight shot attempts. “In the first half he didn’t shoot a free throw. In the second half he shot 17. He’s a hard guy to guard. If you over-react to some of that in the individual and isolation … you foul him it’s definitely three points.”

For Harden, it was his eighth straight game scoring at least 32 points.  And his 9-for-18 shooting performance from three-point range was the most 3’s made and attempted by a Celtics opponent ever.

“Like I’ve said before, it’s the work you put in,” Harden told reporters. “If you don’t put the work in, you won’t get the results. So those moves that I was doing tonight on the court, I was doing yesterday in practice and after practice, after everybody left. So you take those shots, you’re confident in those shots and those shots will go in, sometimes they might not go in. But mostly they’ll go in, and so you have to keep going and keep working.”

Harden draws plenty of praise for his shooting, but what’s often overlooked is how he uses his 6-foot-5, 220-pound frame to create space off the dribble for jumpers or a clearer path to the lane.

Stevens was asked about whether there was a single play that exemplified the physicality of the Rockets roster.

“I’m talking about that every time I watch them play for the last 18 months,” Stevens said. “They’re very physical. (PJ) Tucker and Harden are almost imposible to post. You got guys that are just big, strong guys that are tough all the way up and down that lineup.”

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