Champion Wladimir Klitschko and challenger Bryant Jennings each had a special guest at the weigh-in for their heavyweight title clash, with former champions Vitali Klitschko and Lennox Lewis on hand.

The title holder's older brother was able to take a brief leave from his role as mayor of Kiev in war-torn Ukraine on Friday, while Lewis came to support his friend Jennings in Saturday's championship bout at Madison Square Garden.

The 39-year-old Klitschko (63-3), making his 18th title defence in a nine-year run as heavyweight champion, tipped the scales in the lobby of the Garden at 109.6-kilograms.

"I boxed Klitschko already and [Jennings] just wanted to know a couple of things and I showed him a couple of things," said Lewis, who retired from the ring in 2004.

"He's a friend as well and I'm here to support him."

Lewis's official experience against a Klitschko came versus Vitali, who turned out to be the final professional opponent for the dual Canadian-British citizen.

Lewis won their 2003 bout when the fight was stopped in the sixth round due to a severe cut above the Ukrainian's left eye, though Klitschko was leading on all three judges' scorecards.

In 2001, Lewis acted out fight scenes with Wladimir in the film Ocean's Eleven.

Lewis thinks Jennings, 30, will acquit himself well.

"He's going to do quite well out there. He's a younger man, all he has to try and do is get in there and hit Klitschko.

"Bryant has got youth, agility and speed on his side. The only thing he lacks is experience, and experience comes after many fights."

Another former heavyweight champion, Evander Holyfield, gives Klitschko a decided edge but cautioned against overlooking Bryant, a product of the rough streets of north Philadelphia.

"Everyone in a heavyweight fight has a chance, if you get a shot in," Holyfield said.

"Of course, the pedigree goes with Klitschko. He had a great amateur career and a great professional career.

"But [Jennings] is from Philadelphia. He knows about the Rocky story. Life is about that. You make the best of your opportunity."