By Keith Idec

NEW YORK – Jermall Charlo didn’t need long to show why he was such a huge favorite over Sebastian Heiland.

The hard-hitting Charlo took target practice on the overmatched Argentine southpaw for much of their brief bout Saturday night and stopped him in the fourth round. Heiland suffered a left leg injury early in their scheduled 12-round WBC middleweight elimination match and had trouble keeping his balance before Charlo finished him.

Houston’s Charlo (26-0, 20 KOs) dropped him in the second round and again in the fourth. Heiland (29-5-2, 16 KOs) couldn’t regain his footing once he got up from the second knockdown and referee Benjy Esteves stopped the fight at 2:13 of the fourth round.

“Sometimes the injury can be a decoy,” Charlo told Showtime’s Jim Gray after the fight. “You never want to just jump in and think it’s part of his game plan. My coach [Ronnie Shields] told me to stay behind my job like I did, continue to work and it’s gonna come.”

Showtime televised Charlo’s easy victory in his full-fledged middleweight debut before the main event between Adrien Broner and Mikey Garcia at Barclays Center in Brooklyn.

A hard left hand to the side of Heiland’s head sent him to the canvas in the fourth round.

Two rounds earlier, Charlo floored Heiland with a right uppercut. Heiland reached his feet before Esteves counted to 10, but Charlo connected with numerous power punches for the remainder of the second round.

Heiland made it to the end of the round, but a New York State Athletic Commission doctor checked Heiland’s left leg before he would allow the third round to begin. Heiland seemed to have difficulty planting his right leg in the first round and later his left leg.

The NYSAC doctor checked Heiland’s left leg before the fourth round started as well, yet let the action continue again.

“I turned my left knee in the first round, but I did not want to give up,” Heiland said. “I tried to give it my all, but it was not my night. I had bad luck, but I am going to work harder than ever to get back and get another opportunity to achieve my dream and win a world title.”

Heiland arrived in the ring with a lot of tape around his left knee, which his corner men indicated was from an injury suffered before the fight. NYSAC officials made him remove the tape before the fight started.

Charlo is now the mandatory challenger for WBC middleweight champion Gennady Golovkin. It could take quite some time, however, for Charlo to actually get his title shot.

Kazakhstan’s Golovkin (37-0, 33 KOs) is scheduled to fight Mexican superstar Canelo Alvarez (49-1-1, 34 KOs) on September 16 at T-Mobile Arena in Las Vegas. Alvarez has said he won’t fight for the WBC title, which could complicate matters, particularly if Alvarez beats Golovkin.

“I’m ready,” Charlo said. “Bring on the biggest names at 160. … I’m the real Tommy Hearns. I feel like it’s my turn and I’m gonna get it.”

Heiland had won his previous eight fights, but against a much lower level of opposition than Charlo. He also had been the WBC’s No. 1 contender at 160 pounds for two years before facing Charlo.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.