By Keith Idec

LAS VEGAS – Ryan Martin remained undefeated Saturday night, but Francisco Rojo made Martin work for every bit of his 20th victory.

The relentless, rough Rojo made matters very difficult for the lightweight prospect in the second half of their 10-round lightweight fight, but Martin managed to win a split decision on the Canelo Alvarez-Gennady Golovkin undercard at T-Mobile Arena.

Judges Max DeLuca (95-94) and Lisa Giampa (96-93) scored the fight for Cleveland’s Martin (20-0, 11 KOs), but Richard Ocasio credited Mexico’s Rojo with a wide win (98-91).

Martin’s win was the first of three bouts broadcast by HBO Pay-Per-View before the Alvarez-Golovkin fight. He also won the vacant WBA Intercontinental lightweight title and retained his WBC Continental Americas 135-pound championship.

Rojo had his eight-fight winning streak snapped and dropped to 20-3 (13 KOs).

The taller, rangier Martin began building a lead through the first four rounds by consistently landing his jab and moving to keep out of Rojo’s punching range.

Rojo began catching up to Martin as they traded power shots in the second half of the fifth round. Martin went back to pumping his jab and moving to start the sixth round, but Rojo still had some success with his right hand.

They traded right hands throughout the seventh round, when each fighter had his moments. Martin twice landed low blows that caused brief breaks in the eighth round.

Referee Russell Mora warned Martin both times, but didn’t deduct a point. He also had warned Martin for a borderline blow in the seventh round.

Mora finally took a point away from Martin in the ninth round for another low blow. The point deduction early in the ninth seemed to make Martin fight with a sense of urgency, as he let his hands go for the rest of the round and landed several clean power shots.

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