RJ Barrett’s new approach that could be Knicks’ blessing

LAS VEGAS — RJ Barrett showed a new wrinkle in his repertoire Wednesday and perhaps a way the Knicks may use the 6-foot-7 swingman in his rookie year.

While his perimeter shot was still shaky, the 19-year-old rookie lottery pick out of Duke excelled when given post-up opportunities in his fourth summer league game and took advantage by using his size and strength.

Barrett, in his second straight respectable outing, logged 21 points. He shot just 6-of-17 — 2-for-8 from the 3-point line. He also had 10 rebounds and three assists in 29 minutes as the Knicks posted their first victory, blowing out the Lakers 117-96.

The growth of their No. 3 pick is a massive key if the Knicks are going to…