Roberto Duran, former world lightweight boxing champion,...

Roberto Duran, former world lightweight boxing champion, sued the Internal Revenue Service, disputing a claim that he owes more than $4.54 million in back taxes and penalties for 1977 through 1984.

The IRS contends that Duran failed to report as income almost $12.8 million in boxing earnings during those years. In the suit, filed in Tax Court, Duran disputed the IRS figures and denied owing any back taxes.

In fact, Duran said, the IRS failed to credit him for $1.3 million in taxes that he paid through withholding.