Albert Ramirez remained undefeated Thursday night, but Artur Ziyatdinov tested the touted Venezuelan southpaw during the second half of their 10-round light heavyweight fight.

Ramirez still did more than enough for the judges to score him a unanimous winner of their 10-round co-feature on the Erik Bazinyan-Bill Godoy undercard at Casino de Montreal in Montreal. Judges John Madfis (100-90), Pasquale Procopio (99-91) and David Therien (98-92) all credited Ramirez with winning comfortably, despite Ziyatdinov’s rally during the final five rounds.

The 31-year-old Ramirez improved to 18-0 (15 KOs), but he went the 10-round distance in a second straight fight.

The Uzbekistan-born, Montreal-based Ziyatdinov slipped to 15-2 (12 KOs). The 27-year-old Ukrainian veteran showed, though, that he could complicate matters for a skillful, strong opponent whose punch output was lower during the final few rounds.

Ziyatdinov clearly closed the gap during the second half of their bout, which made both boxers aggressive during a competitive 10th round. Ziyatdinov was warned for hitting Ramirez on the back of his head later in the 10th round.

Ziyatdinov landed a right hand, but Ramirez responded by nailing him with a right hook with just under 2:10 to go in the 10th round.

Ramirez’s straight left backed Ziyatdinov into the ropes barely 20 seconds into the ninth round. Ziyatdinov’s right knocked Ramirez off balance 45 seconds into the ninth round, though, and he made the remainder of that round competitive.

Ziyatdinov landed a sweeping right hand during an exchange 50 seconds into the eighth round. Ramirez was less effective again during the eighth round, which enabled Ziyatdinov to regain some momentum.

Ziyatdinov started the seventh round by fighting off his front foot, which he didn’t do much in the first six rounds. The strategy change didn’t create much success, but Ramirez began slowing down by that point in their fight as well.

A straight left by Ramirez snapped back Ziyatdinov’s head with 1:35 on the clock in the sixth round. Ziyatdinov didn’t seem hurt by that shot once he regained his balance, though.

Ramirez sensed he hurt Ziyatdinov with a left hand about 30 seconds into the fifth round. Ziyatdinov recovered and exchanged with Ramirez later in the fifth round.

Ziyatdinov landed a hard left to Ramirez’s body with just over 1:05 remaining in the fifth round. He also caught Ramirez with a left hook to his head with just under 30 seconds remaining in the fifth round.

A right hook by Ramirez buzzed Ziyatdinov and made him hold Ramirez tightly with 1:40 on the clock in the fourth round.

Ramirez didn’t land as many flush punches during the third round as he did during each of the first two rounds. He did, however, drill Ziyatdinov with a right hook several seconds before the third round ended.

Ramirez rocked Ziyatdinov with a straight left that knocked Ziyatdinov into the ropes with just under 35 seconds to go in the second round. Two left hands Ramirez landed backed up Ziyatdinov barely 30 seconds into the second round.

Ramirez’s straight left moved Ziyatdinov backward 1:15 into the first round. Ziyatdinov spent much of that opening round cautiously getting a feel for the southpaw’s power.

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