Mariusz Ksiazkiewicz Record: 11-2-0

Climbing toward the big stage

By the late 2010s, Ksiazkiewicz had rounded into one of the more complete regional middleweights in Canada. He submitted the experienced Guilherme Miranda with a first-round rear-naked choke in 2019, a statement win over an 18-fight veteran that signaled he was ready for a step up. That earned him a 2020 appearance on Dana White's Contender Series, where he ran into Brazilian Mário Sousa and dropped a unanimous decision – the kind of competitive setback against high-level opposition that did not derail his momentum.

Rebound and the LFA spotlight

Ksiazkiewicz responded to the Contender Series loss the way contenders do. He scored a first-round knockout of Graham Park at Unified MMA 42 in late 2021, then headlined LFA 130 in April 2022 and stopped the 12-3 Alessandro Gambulino in the first round with a knee to the body and punches – a marquee performance that put his name in front of a wider audience. The next outing was a humbling one: Eli Aronov, an undefeated prospect, caught him in a second-round arm-triangle choke at Unified MMA 45 in May 2022. Ksiazkiewicz bounced back in 2024 with a fourth-round TKO of the vastly experienced Rafael Carvalho at Iowa Fight Series 2, showing the resilience that defines his nickname.

Fighting style

Ksiazkiewicz is one of the more balanced finishers on the regional scene, with a near-even split of five knockouts and five submissions among his 11 wins and a 91% finish rate – he very rarely needs the judges. His length and southpaw stance create awkward angles for his striking, while his black-belt jiu-jitsu makes him a constant submission threat, particularly with the rear-naked choke that has accounted for several of his wins. He is comfortable finishing fights standing or on the mat, a versatility that keeps opponents guessing. His losses have come against undefeated and high-level competition, where his measured, methodical pace occasionally left him chasing the action.

Career highlights

• 91% finish rate with a 5-5 KO/submission split — one of the most balanced finishing résumés on the Canadian regional scene.
• LFA 130 headliner — stopped the 12-3 Alessandro Gambulino in the first round in a main-event spotlight performance.
• Dana White's Contender Series veteran — earned a shot on the sport's premier proving ground, sharing the cage with top-tier middleweight prospects.