BOSTON – He dipped into a crouch, ducked into Bradley Beal’s chest and just like that the Wizards’ chances Monday night for a fourth-quarter rally crumbled. A subpar night for John Wall left Beal as Washington’s top offensive option. Boston’s answer: Avery Bradley. The result: a three-point fourth quarter for Beal — and an eight-point Boston win.

Golden State and Portland boast the NBA’s top backcourts, yet this season Boston is making its case to include its duo in the discussion. Isaiah Thomas’ credentials are known: He’s an MVP candidate clawing his way toward a 30-points-per-game season. Bradley? His rep is as a defensive stopper. NBA general managers tabbed Bradley, 26, as the league’s second-best perimeter defender — and you won’t find a coach who disagrees with them. Yet this season he’s nearly a 17-points-per-game scorer. And a 41 percent 3-point shooter. And a six-rebounds-per-game player.

Meet Bradley: The NBA’s most underrated player.

He is. And, really, it’s not close. For years Mike Conley had a stranglehold on the unofficial award. Last summer Conley signed the richest contract in NBA history. Kind of hard to call him underrated now.

Bradley? He’s in Year Three of a four-year, $32 million contract that social media once howled about. Tony Allen gets more pub. In 2014, Bradley was still a tweener, an injury-plagued combo guard still trying to discover an offensive identity. Today he is an elite two-way player whose pre-All-Star break numbers (17.7 points, 6.9 rebounds) had him in the running for an All-Star spot before an Achilles’ injury sidelined him.

Avery Bradley drives against Bradley Beal on Monday night. (AP) More

Surprised? Once, Bradley would have been, too. He almost quit basketball at 15, when he felt he wasn’t hacking it on the AAU circuit. Drafted by Boston in 2010, Bradley was a rookie on a veteran-laden team coming off a Finals appearance that had no time for a defensive-minded guard with a broken jump shot. He barely spoke to his teammates in his first month; he shied away from running plays in practice for fear of incurring Kevin Garnett’s wrath.

He could have folded. He didn’t. He got better. A D-League-heavy first season helped his confidence, and when Boston brought him back, he was ready to play. Toward the end of his first year, Bradley says, he dunked on Kendrick Perkins late in a practice. Then-coach Doc Rivers ended the session there. The next one, Bradley threw one down on Shaquille O’Neal. Same thing. Practice over. He played 21.4 minutes per game in his second year. He was a starter in his third.

Bradley’s approach is simple. “Every summer, pick something in your game that is not as strong and try to improve on it and add something else to try to be effective,” Bradley told The Vertical. In 2013-14, the midrange jumper became a dangerous weapon for him. He was good at it. Too good. He attempted 255 2-pointers from 20 feet or deeper that season. In second? J.J. Redick … with 168. So Bradley locked in on 3-pointers. He attempted 352 threes in ’14-15, making 35.2 percent of them. He’s averaging five threes a game this season, and making them at a 41 percent clip.

Ask coaches — they don’t know what to do with him. “He plays with unbelievable effort,” Hornets coach Steve Clifford said. Indeed, Bradley is indefatigable. He’s always moving and has become deft at rubbing off screens. The influence of Ray Allen? Close. Bradley credits Celtics assistant coach Jerome Allen.

“We watch a lot of film,” Bradley said. “He shows me new moves all the time. He has helped my game go to the next level. We already know what we are going to add next year.”

And that is?

Bradley grinned. “You will just have to wait and see,” he said.

A better Bradley? Celtics coach Brad Stevens would welcome it. He’s already got an elite defensive weapon. Stevens goes into a game with a specific strategy for utilizing Bradley, and has the option of deploying him on the hot hand late in games. Bradley has drawn everyone from Kevin Durant to Russell Westbrook, and given each fits.

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