Irish boxing sensation Pierce O’Leary defends his International Boxing Organization (IBO) World Super Lightweight title tonight, August 1, 2026, against England’s Mark Chamberlain at the 3Arena in Dublin, Ireland. This highly anticipated 12-round main event, presented by Queensberry Promotions, marks O’Leary’s first title defense in his hometown after a significant path to the championship.
The bout was originally set for March 2026 but was postponed when Chamberlain withdrew due to illness. That delay allowed O’Leary to fight and defeat Maxi Hughes for the vacant IBO belt. Now, the stage is set for a compelling rescheduled clash, pitting the unbeaten Dubliner against a determined opponent looking to make his mark.
O’Leary vs. Chamberlain: A Rescheduled Super Lightweight Showdown
Tonight’s main event pits 26-year-old Pierce O’Leary, known as “Big Bang,” with his perfect 19-0 record and 11 knockouts, against the 27-year-old Mark Chamberlain, nicknamed “Thunder.” Chamberlain holds a professional record of 17 wins, 1 loss, and 1 draw, with 12 knockouts.
This fight represents a pivotal moment for both men in the competitive super lightweight division, which has a weight limit of 140 pounds. O’Leary, a highly-rated contender, currently ranks #7 with the WBC, #10 with the IBF, and #9 by The Ring magazine in the 140lb class. Chamberlain also holds a #12 ranking with the WBC in the same division.
Champion’s path to title defense
Pierce O’Leary turned professional in 2019 and has quickly ascended the ranks with his aggressive style. His recent victory over Maxi Hughes to claim the IBO title solidified his status as a top contender and a rising star in Irish boxing. Fighting in his native Dublin adds another layer of expectation and motivation for the champion tonight.
Challenger seeks upset victory
Mark Chamberlain, who debuted in 2018, is a southpaw known for his potent knockout power, boasting a 71% KO rate compared to O’Leary’s 58%. He’s aiming for a strong comeback following a draw in his third fight since suffering his sole professional defeat.
He’ll be eager to upset the hometown hero and claim the IBO title for himself, especially after his earlier withdrawal from their initial scheduled date.
Packed Undercard Lights Up Dublin’s 3Arena
Beyond the main event, the Queensberry Promotions card boasts a compelling lineup of bouts, featuring a mix of rising stars and seasoned fighters. Spectators will witness several intriguing matchups across various weight classes, many of them showcasing local Irish boxing talent.
Key bouts and full lineup details
The chief support bout sees Royston Barney-Smith (16-0, 8 KOs) take on Reece Bellotti (20-7, 15 KOs) for the vacant IBO Inter-Continental Super Featherweight title, scheduled for 10 rounds. This clash promises to be an exciting encounter between an unbeaten prospect and an experienced competitor.
Another highlight features an all-Irish super lightweight clash between Gary Cully (19-2, 10 KOs) and Lee Reeves (16-1, 11 KOs) over 10 rounds. Steven Cairns (14-0, 9 KOs) also faces Senan Kelly (12-1, 2 KOs) in another domestic 10-round super lightweight showdown. Both matchups guarantee competitive action and potential fireworks for the Dublin crowd.
The packed undercard also includes Ben Fail (11-0, 6 KOs) against Craig O’Brien (15-4, 2 KOs) in a super welterweight bout, and Adam Olaniyan (2-0, 2 KOs) taking on Jonathan Claudio Sauco in a heavyweight contest. Sean McComb (21-2, 6 KOs) will face Miguel Cesario Antin at super lightweight.
Further action sees Bobbi Flood (2-0, 1 KO) battle Tariq Davis at super welterweight, while Machlan Arthur (1-0, 1 KO) meets Ryan Frost at welterweight. John Joe Carrigan is slated to fight Sean Murray, and Sami Hamed will compete against Bela Istvan Orban in a super welterweight bout.
How to Watch Tonight’s Dublin Boxing Event
Boxing fans worldwide can tune into the action live via DAZN, the streaming platform. DAZN will broadcast the entire event, including the main card and undercard fights, to subscribers globally. Coverage begins around 4:00 PM local Dublin time, with the main card kicking off at 7:00 PM.
Main event ringwalks for Pierce O’Leary and Mark Chamberlain are anticipated between 10:00 PM and 10:30 PM local time. Viewers have multiple options for accessing the stream, including the DAZN App on smart TVs, phones, tablets, streaming devices, and game consoles.
Amazon Prime Video subscribers can also access the fight through the DAZN channel on their platform. The event will not be available on traditional broadcasters like Sky Sports or TNT Sports.
Stakes are High for Both Fighters
For Pierce O’Leary, a victory tonight would not only mark a successful first defense but also propel him further up the super lightweight rankings. Maintaining his unbeaten record against a tough opponent like Chamberlain is crucial for securing marquee fights against other champions or top contenders in the future. His stock would rise considerably.
Conversely, for Mark Chamberlain, winning the IBO title would be a monumental achievement, erasing the memory of his previous illness and solidifying his position among the division’s elite. It would significantly boost his career trajectory and put him on course for more high-profile bouts.
The outcome of this fight will undoubtedly have a ripple effect throughout the super lightweight landscape, influencing future matchups and title challenges. Both fighters understand the gravity of the situation, making for a potentially explosive encounter in front of a passionate Dublin crowd.
The 3Arena is set to witness a defining night for both O’Leary and Chamberlain as they vie for supremacy in the IBO super lightweight division.
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