by David P. Greisman

Cornelius White’s loss to Sergey Kovalev wasn’t the first time he was knocked out, but that defeat taught him a crucial lesson.

“That you never go in underestimating someone's power,” White said Thursday on an ESPN.com chat promoting his bout against Thomas Williams Jr. on ESPN2’s Friday Night Fights. “They could be a strong guy or a weak guy, you don't underestimate. You never underestimate your opponent.”

White, 32, is 21-2 with 16 knockouts. The Kovalev loss, a third-round technical knockout, came last June in an elimination bout for a light heavyweight title shot. White’s only other defeat was a first-round stoppage against Donovan George  in February 2011, a bout that was White’s last appearance at super middleweight.

“His power is unreal,” White said of Kovalev. “I've never felt that power before. I've fought heavyweights, cruiserweights and I've never felt that before. And they weren't bricks. It was steel.”

White-Williams will be the main event of a broadcast airing from the Little Creek Casino in Shelton, Wash. “Friday Night Fights” begins at 9 p.m. Eastern Time

Williams, 26, is a prospect with a record of 15-0 and 10 knockouts. His last bout was on Nov. 26 and was a 10-round decision win over Yusaf Mack.

A full transcript of White’s chat can be found at http://espn.go.com/sportsnation/chat/_/id/49873/friday-night-fights-chat

Pick up a copy of David’s new book, “Fighting Words: The Heart and Heartbreak of Boxing,” at http://bit.ly/fightingwordsamazon or internationally at http://bit.ly/fightingwordsworldwide. Send questions/comments via email at fightingwords1@gmail.com