Jaylen Brown Cops $250k Emerald Chain Ahead of Celtics' Playoff Run

Jaylen Brown just got something incredible to complement his Celtics championship ring ... a $250k chain with an emerald centerpiece right before his quest for another title!!

TMZ Sports has learned ... the Boston star wanted to get a special accessory to embody his  mantra, "The energy is about to shift," so he hit up Eric The Jeweler for the job.

Of course, there's a double meaning here ... as a green emerald symbolizes energy, while also a nod to his team's iconic colors. Eric, who has also worked with rapper Playboi Carti, executed the task to perfection.

The chain is crafted from 18k rose gold with over 50 carats of white diamonds ... and features a stunning 200-carat green emerald to bring it all together.

The big price tag is pocket change for the four-time NBA All-Star ... who signed a five-year deal with Boston, worth up to $304 million.

Last year, 28-year-old Brown led the Celtics to their first NBA Championship since 2008 ... and earned NBA Finals MVP after averaging 20.8 points and 5 assists per game against the Dallas Mavericks.