John Lineker’s seven-year run with ONE Championship has officially come to an end following a failed drug test and a one-year suspension.
The former ONE bantamweight MMA champion tested positive for tamoxifen and metandienone after his March 2026 kickboxing loss to Ben Woolliss at ONE Fight Night 41.
According to reports, tamoxifen is classified as an anti-oestrogenic substance, while metandienone — also known as Dianabol — is an anabolic androgenic steroid.
The drug test was reportedly conducted on March 14, one day after the fight in Bangkok, and the results came back positive on April 10. ONE Championship handed John Lineker a one-year suspension that runs until April 9, 2027.
Following the suspension, ONE Championship and John Lineker officially parted ways.
The 35-year-old Brazilian entered the Ben Woolliss fight on a difficult run, having already lost three straight bouts before the defeat. His recent struggles marked a sharp contrast from the dominant run that once made him one of the promotion’s biggest stars.
John Lineker joined ONE Championship in 2019 and quickly became one of the most dangerous fighters on the roster. He captured the bantamweight title in March 2022 after stopping Bibiano Fernandes with a second-round knockout.
However, his reign quickly unraveled. John Lineker later lost the belt on the scale after missing weight for a scheduled title defense against Fabricio Andrade. Their first meeting ended in a no-contest before Andrade stopped him in the rematch in February 2023 to claim the vacant title.
Since then, “Hands of Stone” struggled to regain momentum.
John Lineker went 6-2 with one no-contest in MMA under the ONE banner between 2019 and 2024. He later transitioned into striking bouts, posting a 2-1 record in Muay Thai and an 0-2 record in kickboxing competition.
Despite the suspension, John Lineker is still scheduled to compete in a boxing match against Rogerio Ferreira on June 6 in Curitiba, Brazil.
ONE Championship also released several other fighters from its roster, including Danny Kingad, Kang Ji Won, Eddie Abasolo, Ali Saldoev and Taylor McClatchie.
Danny Kingad exited the promotion after three straight losses, while Kang Ji Won left with a 4-4 record following back-to-back defeats. Eddie Abasolo also departed after losing three consecutive fights during his short ONE Championship run.
For John Lineker, the failed drug test closes another difficult chapter in what was once one of the most exciting careers in MMA.
