BOSTON – Al Horford stood beyond the 3-point line with his back to the basket and his arms draped all over DeMarcus Cousins as the final seconds of Friday’s game between the Celtics and Kings ticked away.

Sacramento trailed 95-92. The shot clock was off and the game clock trickled down from nine seconds… to eight… to seven.

Cousins had no option but to go for the tie. The only problem was that Horford was giving him no room to breathe.

Sacramento’s star big man rose up for the potential game-tying shot, but could not even manage to bring the ball above his waist. Horford’s right forearm got in the way, making solid contact with the rock for his season-high sixth block of the game.

The ball spun back into Horford’s hands; he was then fouled and made both of his free throws for his 25th and 26th points of the night, sealing a hard-fought, 97-92 win for the C’s.

The 26 points were also a season-high for Horford, but his scoring ability comes to no shock. He’s always been offensively adept, and that was one of the many reasons why the Celtics targeted him during free agency period this past summer.

What was surprising was Horford’s dominating presence on the other end of the floor, highlighted by his last-second swat with the game on the line.

“I thought there were a couple of huge plays that he made, blocking shots,” C’s coach Brad Stevens said after the game. “The one thing about Al is he’s always in a stance. His arms are always long. He takes up a lot of space and then he reacts quickly to what’s going on.”

The 30-year-old big man has always been a fairly solid rim protector; he entered this season with a career average of 1.2 blocks per game during his nine years with the Atlanta Hawks.

But he’s been a completely different animal in that aspect for the Celtics, not only Friday night, but during each of the nine games he has played in this season.

Horford has blocked at least one shot during every contest and has recorded multiple swats in all but one game.

With his six blocks Friday night, Horford moved ahead of Anthony Davis for the league lead in blocks per game (2.9 BPG).

So, why the sudden surge? What is allowing Horford to more than double his career shot-blocking rate? He believes it’s largely due to the fact that he’s playing more power forward in Boston, which is allowing him to use his quickness and length to contest shots over a vast area.

“I think that playing at the power forward position really frees me up defensively,” said Horford, who finished one block shy of his career high. “I feel like I can run around a little more and have more impact.

“When you’re a center, a lot of the times you get caught up with the bigs and it’s a little harder to get out to shooters and stuff. I’m just trying to be active, as active as I can.”

Boston has needed an active rim protector for years, and Isaiah Thomas says Horford perfectly fits the role.

“We’d always known when we recruited him, we knew that’s what he was good at,” said Thomas. “Even if he doesn’t block shots, he alters shots and changes them. He’s a hell of a player on both ends of the floor, and he played a hell of a game tonight.”

“A hell of a game” may be an understatement.

Not only did Horford block shots and score; he also corralled eight rebounds, snagged two steals, dished out three assists and only turned the ball over once during a game-high 36 minutes of play.

According to basketball-reference.com, he became the first NBA player on record to tally at least 26 points, four 3-pointers, six blocks and two steals in one game.

And he did all of this against one of the best centers in the league in Cousins.

Cousins entered Friday’s matchup riding the hottest stretch of his career, having averaged 35.3 points and 13.3 rebounds during his previous four games. He tallied 28 points and nine boards Friday night against the Celtics, and missed 16 of his 26 shot attempts.

A large percentage of those misses came while Horford was defending Cousins, including the game-deciding block during the closing seconds.

Horford rose to the occasion, quite literally, when the Celtics were in need of his shot-blocking prowess. And don’t expect it to be the last time that he does so, considering the way he’s been protecting the rim and swatting away the competition of late.