Sergey Kovalev called Adonis Stevenson "just a talker," and welcomes a shot at the winner of the 175-pound unification bout between IBF light heavyweight beltholder Bernard Hopkins and WBA counterpart Beibut Shumenov.

The current WBO titleholder, Kovalev (23-0-1, 21 knockouts), 30, was responding to criticism that he has received recently from Stevenson, Hopkins and Shumenov.

Stevenson (23-1, 20 KOs), 36, ripped Kovalev's "weak chin" and "terrible" defense during an interview with RingTV.com. Stevenson has May 24 defense of his RING and WBC championships against Andrzej Fonfara in the works.

"No one is scared of your sorry ass…If the money is right, I will be more than glad to come give you a good ass-whooping in the ring," said Stevenson, in part, about Kovalev. "Besides having power, you have nothing special. Your defense is terrible, and it won't be to hard to find your big ugly head with that long-ass chin."

Kovalev is 11-0-1 with 11 stoppages in his past 12 bouts, and will face unbeaten Cederic Agnew on March 29 in Atlantic City. 

"I am not going to spend any more of my time talking about him," said Kovalev, in statements provided to RingTV.com by Main Events. "If he is a real champion and wants to prove he is the best, let's meet and let our fans to decide who is the best. If he is just a talker, let him talk."

Meanwhile Hopkins (54-6-2, 32 KOs), who will face Shumenov (14-1, 9 KOs) on April 19 in Washington, D.C., told RingTV.com "I would easily beat Kovalev."

"That would be the easiest fight. That fight, for me, would be just as easy as beating Kelly Pavlik," said Hopkins, 49, who is coming off a unanimous decision over Karo Murat in October.

"That fight would be real easy. Less than easy. If not, easier — and don't forget to put that 'Er' on the end of that word — than the Kelly Pavlik fight. I'm telling you."

In addition, Shumenov, 30, has dismissed both Stevenson and Kovalev in comparison to Hopkins.

"Stevenson and Kovalev just recently became world champions, and they haven't done anything yet to claim they are the best in the division," said Shumenov, during an interview with RingTV.com.

"While Hopkins, I consider him the best champion in our weight division. He is a boxing genius and a legend. That's why I want to fight the best."

Kovalev expressed the desire to face either Hopkins or Shumenov should he get beyond Agnew and, later, perhaps a heavily-anticipated bout against Stevenson.

Stevenson and Kovalev are aligned with Showtime’s network rival, HBO, which has severed ties with Golden Boy, the promoter of Hopkins and Shumenov.

"Talking is cheap. We know how Hopkins likes to talk. I would like to see him in the ring to prove what he is talking," said Kovalev.

"Me and my manager liked the idea of Beibut. He will fight Hopkins and I will fight Stevenson, winners of these two bouts will meet for unification of four belts. It would be very good if our promoters and TV network can put this together."

AUSTIN TROUT ASSESSES SERGIO MARTINEZ-MIGUEL COTTO

RING middleweight champion Sergio Martinez vows to severely punish Miguel Cotto, who will be fighting as a 160-pounder for the first time when they meet on June 7 at Madison Square Garden.

Cotto was last in the ring in October, when he knocked out Delvin Rodriguez in the third round to bounce back from a unanimous decision to Austin Trout in December 2012.

Trout is a southpaw like Martinez, for whom he served as a sparring partner in preparation for Martinez's eighth-round stoppage of Sergei Dzinziruk. Martinez scored five knockdowns against Dzinziruk.

In assessing Martinez-Cotto, the nearly 5-foot-10 Trout said Cotto was troubled by his size, while 5-10 Martinez was hindered in sparring by his jab. 

Trout also noted that although Martinez has been known to ravage and bloody his rivals' faces, he has also had to rise from the canvas during each  of his past three victories, received eight stitches to repair a cut over his left eye, two staples in his head, and suffered from both a broken left hand and torn ligaments in his right knee.

Martinez has had two surgeries on his knee.

"There's no question that Martinez is the bigger man. If I was Martinez, I would work the jab and make Cotto work to get in, mixing it up when he wanted to. I think that maybe he's got to box and move. He can take it to him and maybe try to impose his size on him. I those might be a couple of things that he might try, being the bigger guy," said Trout.

"For Cotto, I would tell him to keep the jab on him, don't let Martinez get set, and to fire off first. You have to remember that Martinez has been injured, and this is his first fight back from being injured. Is that a factor? Another one of the big questions is whether Martinez is too old, and whether or not his size is going to be a factor. It's going to be a great fight."