The U.S. Anti-Doping Agency (USADA) announced Wednesday that UFC lightweight Islam Makhachev had been found "without fault or negligence" for an out-of-competition drug test administered on April 4 that popped positive for the banned substance meldonium. As a result, Makhachev will not face further punishment for his positive test.

Makhachev, 24, was flagged for an out-of-competition urine sample and pulled from competition the day before his April 16 fight against Drew Dober at UFC on FOX 19. USADA formally lifted Makhachev's provisional suspension in early July but continued to investigate the failed test.

USADA ultimately ruled that Makhachev's testing failure stemmed from a "radiofrequency ablation procedure for frequent ventricular arrhythmia" the fighter underwent in Dec. 2014. As part of a follow-up treatment plan, Makhachev's physician recommended the fighter take meldonium "as a preventive measure against a potential relapse" in Nov. 2015. Makhachev then took meldonium for four weeks but stopped his use prior to Jan. 1 2016, the date meldonium was added to the WADA banned substance list.

"After a thorough review of the case, USADA concluded that the extremely low meldonium concentration in the athlete's urine sample, combined with the athlete's explanation of use, was consistent with ingestion prior to the substance being officially prohibited on January 1, 2016," the organization announced in a statement. "Based on the latest guidance offered by WADA on June 30, 2016, for cases involving meldonium, Makhachev will not face a period of ineligibility for his positive test."

Makhachev (12-1) is currently scheduled to face Chris Wade on Sept. 17 at UFC Fight Night 94 in Hidalgo, Texas.

The Dagestani lightweight holds a 1-1 record under the UFC umbrella, having submitted Leo Kuntz with a second-round rear-naked choke in his Octagon debut, then suffered a first-round knockout loss to Adriano Martins at UFC 192.