Lenier Pero abruptly and stunningly ended his heavyweight fight with Viktor Faust late in the eighth round Saturday night in San Antonio.

After taking a right hook to the body and a straight left to his head, Faust turned his back to Pero, which left referee Rafael Ramos no choice but to stop the action at 2:28 of the eighth round. Their scheduled 10-rounder was very competitive prior to Pero’s technical knockout win in the opener of Showtime’s tripleheader from Alamodome.

Ukraine’s Faust (11-1, 7 KOs) was much more active for seven-plus rounds and wobbled Pero just before the third round ended. Judges Ruben Carrion (68-65) and Alejandro Rochin (67-66) had Faust in front through seven rounds.

Cuba’s Pero, who was ahead 68-65 on judge Tim Cheatham’s scorecard entering the eighth round, ensured that they didn’t go to the cards. The strong southpaw instead improved to 9-0 by producing his sixth knockout.

“Since the first round, we were trying to find his liver, trying to go to his body,” Pero told Showtime’s Brian Campbell in the ring. “His punches weren’t that powerful, so we kept working and then we found that final shot.”

CompuBox credited Pero for landing more punches overall than Faust, despite Faust’s impressive activity. According to CompuBox, the more accurate Pero landed 92-of-183 punches overall, 10 more than Faust (82-of-389).

Pero landed a left hand to the center of Faust’s face just after his right hook to the body, which made him wince and turn his back on Pero in the eighth round. Ramos stopped the fight several seconds later, after Faust leaned over on the top rope.

“This is pro boxing and you can’t turn your back on anyone,” Pero said. “You can’t turn your back, and I didn’t, and I took advantage.”

A straight left by Pero jarred Faust about 35 seconds into the eighth round.

Pero was active with his straight left during the seventh round, when Faust mostly worked off his jab.

Pero’s left to Faust’s wide-open body connected with just over 50 seconds to go in the sixth round. Pero landed a low blow about 25 seconds later, which caused a brief break in the action.

A counter left hook by Faust caught Pero and made him hold 1:20 into the fifth round.

Faust’s right hand snapped back Pero’s head with just under 1:15 on the clock in the fourth round. Faust and Pero traded power punches about 50 seconds into the fourth round.

A counter left hook by Faust made Pero stumble just before the third round concluded.

Faust’s overhand right connected with just under a minute remaining in the third round. Faust’s right hand landed just before the halfway point of the third round.

Pero and Faust traded hard shots just before the second round ended. Another counter left by Pero landed with just over a minute to go in the second round.

Pero countered Faust with a straight left that landed a little less than a minute into the second round. Faust’s right hand landed barely 45 seconds into the second round.

Pero clipped Faust with a right hook that connected with just under 50 seconds to go in the first round. Pero held his guard high for most of the first round, when Faust tried to penetrate Pero’s defensive stance with his jab.

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