In his next fight, Kalambay defeated future three-weight world champion Iran Barkley by unanimous decision over fifteen rounds to win the vacant WBA middleweight title.
He made three successful title defenses, including an upset unanimous decision win over Mike McCallum,[1] the undefeated former WBA light middleweight champion.
In March 1989, at the Hilton Hotel, Las Vegas, Nevada, United States, he boxed undefeated IBF middleweight champion Michael Nunn, being stripped of the WBA belt prior to the bout.
Kalambay made four more successful defenses of the European title in Italy, including a rematch win over Herol Graham, and a points victory over future two-weight world champion Steve Collins.
In May 1993, at Granby Halls, Leicester, East Midlands, England, Kalambay lost by unanimous decision to Chris Pyatt in a challenge for the vacant WBO middleweight title.