Portland native Russell Lamour Jr. was unable to capture the vacant IBA North American middleweight championship in the main event Saturday night at the Portland Expo.

The event was hosted by the Portland Boxing Club, which welcomed former Olympic gold medalist and world heavyweight champion Ray Mercer and former Boston Bruin Rick Middleton as special guests. Mercer was presented with a key to the city by Mayor Ethan Strimling.

Lamour (15-3), who lost the North American middleweight belt in 2015, dropped an eight-round split decision to John Thompson (18-3) of Newark, New Jersey.

Thompson opened a cut over Lamour’s left eye near the end of the first round. Lamour opened a cut on Thompson’s nose in Round 4.

South Portland resident and Portland firefighter Jason Quirk remained unbeaten as a pro. Quirk, a super middleweight, improved to 8-0 with a fourth-round knockout of Siri Mikael Bosse of Charleston, West Virginia.

Quirk controlled the pace throughout the contest and started to land heavy body shots midway through Round 2. He scored his sixth knockout as pro with a devastating right hook that ended the fight 1:15 into Round 4.

Brandon Berry of West Forks, a welterweight fighting for the first time since shoulder surgery a year and a half ago, fought to a majority draw in a six-round match against Eric Palmer of Uniontown, Pennsylvania.

After being knocked down twice in the opening round of his light heavyweight fight against Austin Marcum of Charleston, West Virginia, Brandon Martella of Woburn, Massachusetts, responded with a TKO 2:17 into the third round.

Tommy Karpency of Youngstown, Ohio, scored a first-round TKO at the 1-minute mark in his cruiserweight fight against Rubin Williams of Detroit.

Lewiston’s Christiano Pedro earned a TKO over John Hantzoupolas of Carver, Massachusetts, as the referee stopped the fight just 39 seconds into the contest.

Josniel Castro, a Portland native, won a three-round decision in an amateur welterweight bout against Tim Lawrence of Red Bank, New Jersey.

In a women’s amateur fight, light welterweight Lindsay Kyajohnian Francois of Portland dropped a three-round decision to Shelly Walsh of Boston.