By Lem Satterfield

Jermall Charlo’s piston jab is perhaps the most dangerous and important punch in his repertoire, having been the beginning of the end for opponents at least three times during his stellar career.

Charlo’s jab caused the second of three knockdowns during his IBF 154-pound championship victory that dethroned Cornelius Bundrage by third-round TKO on September 12, 2015, exactly seven years to the day from his pro debut.

“The Hit Man’s” signature blow also caused the first of three knockdowns during fourth- and fifth-round stoppages of Wilky Campfort (November 2015) and previously unbeaten Julian Williams (December 2016) for Charlo (27-0, 21 KOs), a 28-year-old with five knockouts in his past six fights.

“The jab sets up a lot of my arsenal and a lot of my other attributes, so once they think they’ve figured out my jab, I got a lot of other weapons waiting for them,” said Charlo, who trains under Ronnie Shields at The Houston Texas-based Plex Gym, to BoxingScene.com.

“A lot of fighters have had a lot of problems just getting past my jab, alone, and I’ve continued to work with Ronnie on executing it with precision the way I’ve been doing.”

That punch will no doubt be on display on December 22 at Barclays Center in Brooklyn, New York, where Charlo (27-0, 21 KOs) will pursue his first defense of his interim WBC middleweight crown and fourth straight knockout against southpaw two-time title challenger Willie Monroe (23-3, 6 KOs). Charlo’s twin sibling, Jermell (31-0, 15 KOs), will also defend his WBC junior middleweight crown against repeat title challenger Tony Harrison (27-2, 21 KOs).

“Ronnie and I have a game plan to remain at the top, and the key point and the start of that is the jab,” said Charlo.  “The secret? It just comes so naturally that I don’t even have to think about it. I’m still improving it.”

Jermall Charlo vacated the 154-pound title after defeating Williams, who represented his third defense and followed a unanimous decision over left-handed former titleholder Austin Trout in May 2016.

Charlo is making his third straight appearance at Barclays, where his 160-pound debut was July’s two-knockdown, fourth-round TKO of Argentina’s Jorge Sebastian Heiland, who was stopped for the first time in his career.

In his last fight in April at Barclays, the 6-foot Charlo flattened 6-foot-1 Hugo Centeno (26-2, 14 KOs) with a frighteningly devastating second-round left hook to become the WBC’s interim 160-pound champion.

 “Hugo Centeno’s tall, so in the first round, I told Jermall to box him and make him think this is how you’re gonna fight. But in the second round…I said, ‘Now go and jump on him, right now,’” said Shields.

“So that’s exactly what Jermall did. I knew that as soon as Jermall touched him he was gonna knock him out. Jermall has power in both hands, and has been hurting and dropping guys with his jab for his entire career.”