David Morrell Jr. dismantled Sena Agbeko in the second round Saturday night at The Armory in Morrell’s adopted hometown of Minneapolis.

Morrell blasted Agbeko with a barrage of power punches that forced referee Mark Nelson to step between them to protect a vulnerable Agbeko. The official time of the stoppage was 1:43 of the second round.

The Cuban-born Morrell, who was a 14-1 favorite, improved to 10-0, produced his ninth knockout and retained his WBA secondary super middleweight title in the main event of the final “Showtime Championship Boxing” broadcast of the network’s 37 years in the sport. The Ghanaian-born, Nashville-based Agbeko (28-3, 22 KOs) lost by knockout for the second time as a pro.

Morrell staggered Agbeko with a left hand that connected with about 1:25 to go in the second round. A defenseless Agbeko took several additional flush punches before Nelson stepped between them to halt the action.

Morrell’s left and right landed with just under two minutes on the clock in the second round.

A right hook by Morrell knocked Agbeko off balance barely 10 seconds into the second round. Agbeko landed a right hand several seconds later, though, and temporarily kept Morrell off of him.

Morrell’s straight left landed when Agbeko backed into the ropes with just under 20 seconds remaining in the first round. A straight left by Morrell backed up Agbeko with under 1:20 to go in the first round, but Agbeko fired back and landed a right hand of his own.

Morrell landed a right hook and then a straight left less than 30 seconds into the opening round.

Morrell, 25, and Agbeko, 31, were first scheduled to fight April 22 at T-Mobile Arena in Las Vegas.

The Nevada State Athletic Commission denied Agbeko’s license application for that bout because a saccular brain aneurysm was detected during an MRI administered a few weeks before he was set to meet Morrell. Two neurologists later cleared Agbeko and the NSAC licensed him early in May, a couple weeks after Morrell overwhelmed Agbeko’s late replacement, Brazil’s Yamaguchi Falcao, in the first round on the Showtime Pay-Per-View portion of the Gervonta Davis-Ryan Garcia undercard.

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