Knockout may be Sergey Kovalev’s only route to defeating Andre Ward

Sergey Kovalev said he intends to “punish” Andre Ward in their June 17 rematch at Mandalay Bay in Las Vegas.

He better do more than that.

The former three-belt light-heavyweight champion from Russia either needs to knock out Oakland’s new champion Ward, or face a fate crueler than Ward’s narrow unanimous-decision triumph over Kovalev in November.

In that bout, Kovalev (30-1-1, 26 knockouts) dropped Ward early and contended in several close rounds afterward. Yet, judges granted Ward (31-0) the victory.

Now, with no rematch clause in effect, Kovalev finds himself in a do-or-die predicament, and “do” is scoring a knockout.

“I’ll be in my best shape. I just have one goal: to beat Andre Ward,” Kovalev said. “He doesn’t deserve the belts.”

Nevada regulators have already let it be known they’re not going to be swayed by the calls of the Kovalev camp for an international judge to be added after an all-U.S. panel gave Ward the victory in the fall. Kovalev said in his only review of the bout that he believed he won eight of 12 rounds.

The last time Nevada became so dug in after controversy, it put judge C.J. Ross back in a big fight after her atrocious scoring in a Timothy Bradley victory over Manny Pacquiao. Ross returned to give Canelo Alvarez a tie score in a convincing Floyd Mayweather Jr. victory.

This time, Americans Glenn Feldman, Dave Moretti and Steve Weisfeld will have the scorecards. Great judges all, and all men who have awarded a sophisticated boxer the benefit of the doubt over a puncher in close rounds.

Ward, America’s last male Olympic boxing gold medalist, knows precisely what they want to see, having done it from the fifth round on seven months ago. He’ll box smart, stay just busy enough and avoid Kovalev’s biggest shots.

Kovalev has to no choice other than find a way to inflict major damage.

“I’m ready for everything Ward gives me. I believe the judges will do their best job, what they should do,” Kovalev said. “Andre Ward is the one who needs to prove he’s the real champion. I’m going to punish him and get my belts back.”

Kovalev trainer John David Jackson said the only major adjustment is to fight “more aggressive” in the second half of the fight while seeing if Ward will fight differently.

“What adjustments can Ward make? He can’t be more aggressive … or run more. If he does, that works more in our favor,” Jackson said. “He needs to be more aggressive to prove he won that first fight outright. How much smarter can he be? He can’t be any more brilliant.

“He does what he does – surviving, winning ugly … and he received points for that. Can he improve? Not really. … The adjustments will not make him a more dominating, aggressive fighter. If he does that, then he’s playing Russian roulette and he’s going to get clipped.”

Still, that’s a substantial task for Kovalev given that it didn’t happen in the 12 prior rounds, while Ward is armed with the institutional knowledge of how to best avoid the heaviest of blows.

Kovalev said recently he over-trained for the first bout and found his “energy bag was empty” one month before the fight, and it showed in the second half of the bout.

“I feel good, much better, and you’ll see June 17,” Kovalev said. “This fight will be much different and much better.”

lance.pugmire@latimes.com

Twitter: @latimespugmire