Jermell Charlo's quest to become the unified light-middleweight champion is on hold after he fought to a controversial split draw with Brian Castano in Texas on Saturday. 

The American Charlo (34-1-1), holder of the WBC, WBA and IBF belts, got a tougher fight than many expected from the Argentine, who holds the WBO strap at 154 pounds and was the aggressor from the start in San Antonio. 

Castano's overall effort was enough to earn him a 114-113 win on judge Steven Weisfeld's scorecard and a 114-114 draw on Tim Cheatham's, but Nelson Vazquez scored the fight 117-111 for Charlo, who rallied in the later rounds. 

"The draw wasn't what I wanted to hear," Charlo told Showtime in the ring afterward. "If anything, I won this fight. I hurt him way more than he did [me]. Brian Castano's a tough warrior, he going to give a lot of people problems, but my power is something serious at this weight division."

While Charlo's power left Castano (17-0-2) unsteady a couple of times in the fight, it was hardly overwhelming. 

The American's coach, Derrick James, made it clear to Charlo in the later rounds that he had to get a knockout to be assured of victory, but Castano stood strong for the duration to earn the draw. 

"I won the fight," Castano said through an interpeter. "There were some rounds he hit me hard, but I won the fight.

"I hope there's a rematch. He's a great fighter -- me, too. I need the rematch." 

Key moment

Despite the lopsided scorecard in his favour, Charlo may have salvaged the draw with a strong 10th round that left Castano on the defensive, attacking the Argentine relentlessly in search of the finishing blow. 

What happens next? 

A rematch figures to be in the offing, though Australian challenger Tim Tszyu tweeted after the draw that he was ready for a fight with Castano.