Celtics vs. Knicks Game 5: Too much Jaylen Brown and… Luke Kornet? Yes, and Celtics force Game 6

Through the first four games of this series, Kristaps Porzingis struggled with his health and game. He was shooting 27.8% (and 20% from 3), was not a defensive presence in the paint, and was generally just a step slow while playing through a respiratory issue.

Shorthanded without Jayson Tatum, Joe Mazzulla tried to stick with him and started Porzingis next to Al Horford in Game 5, but by the middle of the second quarter Porzingis was -14. That’s when Mazzulla essentially benched him — and Luke Kornett was everything Boston needed. He was a defensive force with seven blocked shots, plus he scored 10 points.

Combine Kornet with the Jaylen Brown from last playoffs — 26 points, 12 assists and eight rebounds — and the Celtics pulled away in the third quarter and cruised to a 127-102 win.

That win extended the Celtics’ season and forced a Game 6 on Friday night at Madison Square Garden. New York still leads the series 3-2 and can earn its first trip to the Eastern Conference Finals in 25 years with a win.

The game changed in the third quarter when the Celtics didn’t just settle for 3-pointers and started getting downhill in the paint and started drawing fouls. Boston got to the free-throw line 18 times in the third quarter, and Jalen Brunson picked up four fouls, limiting his impact. Brunson and Karl-Anthony Towns were in foul trouble and on the bench watching Boston get out and run off the 16 missed Knicks shots that quarter (4-of-20).

Boston was moving the ball, not settling for isolation shots in a crowd, and getting downhill. This was the Celtics offense their fans had been waiting to see — Derrick White finished with 34 points, Brown 26 and Payton Pritchard 17 off the bench.

The Celtics shot the rock well all night — they shot 50% overall in the first half and were 12-of-25 on 3s, with White and Brown leading the way with a combined 36 points. The concern was that despite all that, the game was tied at halftime and the Knicks had been the better team down the stretch this series.

Not on Wednesday. Even without Tatum — who is out for the series after rupturing his Achilles in Game 4 — the Celtics played their best game of the series.

Now they have to do it two more times to advance. Whether Boston can sustain that level of execution without Tatum is the question.