Terence Crawford survived some early jitters to retain his WBO welterweight title on Saturday with a ninth round knockout of former Olympian Egidijus Kavaliauskas at Madison Square Garden.

Crawford, who improved to 36-0 with 27 knockouts, survived a scare in the third round before finding his rhythm in the fifth, knocking the Lithuanian down once in the seventh, and then twice in the final round.

In a tougher than expected tussle, Crawford finished the heavy underdog challenger off with a right hook to the left ear 44 seconds into the ninth.

“When I let my hands go that's when I started landing more favourable shots,” the American said.

“After I dropped him with my uppercut I was like, I am going to face his jab, and come out with my right hook.

Kavaliauskas barely survived the end of the eighth round and Crawford wasted no time going to work in the ninth. He landed a barrage of punches to start the round, beginning with a left hook followed by a right that sent Kavaliauskas staggering back towards the ropes.

Crawford then moved in for the finish and connected with a right hook that floored Kavaliauskas (21-1-1, 17 KOs) for the third and final time as the referee stopped the bout.

Kavaliauskas, who competed in the 2008 and 2012 Olympics, appeared to score the first knockdown of the fight in the third round. But the referee ruled that Crawford slipped. Regardless Crawford was in a load of trouble after absorbing an overhand right on the chin.

Crawford collected his thoughts and survived the round, but it wasn't until the fifth that he really started to look like his old self.

Crawford's early troubles aside, he did a superb job of figuring out a tough opponent who came into the bout in excellent shape.

“He's a strong fighter, durable,” said Crawford who denied he was in trouble in the third. “I wasn't hurt at all. I went straight for him. He caught me with a good punch.

Crawford and his promoters are hoping to eventually land a fight with former two-time welterweight champ Shawn Porter.

Whoever he fights it will surely be a much bigger test, which means Crawford can't afford to fiddle away five rounds before he gets comfortable throwing meaningful combinations.

“The rounds before my coaches were telling me to stop loading up. I was trying to give the crowd a knockout,” he said.

“I am not ducking anybody. Listen man, everybody knows who I want to fight. I don't have to name names. I want all the top guys.

On the undercard, Teofimo Lopez captured his first world title by knocking out Ghana's Richard Commey in the second round to take Commey's IBF lightweight crown in emphatic fashion.

“I'm at a loss for words right now. This is a dream come true,” said Lopez, 15-0 with 12 KOs.

“[Commey] is a bad man. His shot could've done the same to me if he hit me with that shot.

Veteran Commey (29-3, 26 KOs) suffered just his third career loss but he had never been dominated by an opponent like this before.

Commey was making his second title defence and looked solid in the opening round, but then Lopez destroyed him in the second.