Kyodo News reports that the suspension, handed out by the Japan Boxing Commission, has been backdated to December 10 - the day after Ogawa beat United States' Tevin Farmer on a split decision to claim the then-vacant International Boxing Federation super featherweight title.

Last month, the result of the fight in Las Vegas was nullified after it was confirmed Ogawa tested positive for two forms of androstanediol, a synthetic testosterone, in a urine test conducted on December 5.

As well as changing the split decision victory to a no contest, the Nevada State Athletic Commission (NSAC) also imposed a six-month ban on Ogawa, who is the first Japanese boxer to be stripped of a world title. 

A drug test after the fight had come back negative.

Ogawa denies knowingly ingesting a banned substance and according to Kyodo News, a source close to the matter claims medicine for the 30-year-old’s skin condition could have caused the failed test. 

The medication has been submitted to the NSAC by Ogawa.

The failure marks another blemish on Japan's previously good anti-doping record which was widely celebrated in the build-up to their home Tokyo 2020 Olympics.

Tokyo bid officials claimed in 2013 that no Japanese athlete had been implicated in a doping scandal in the latter stages of a contest against Istanbul and Madrid - bids from two countries who had each faced a multitude of failures.

But Japanese kayaker Yasuhiro Suzuki was banned for eight years in January after he admitted spiking a rival's drink with an outlawed substance.

Suzuki laced Seiji Komatsu's bottle of water with an anabolic steroid to ensure he failed a drugs test at the Canoe Sprint Japan Championships last year.

Japanese short-track speed skater Kei Saito then became the first athlete embroiled in a doping scandal during the Winter Olympics in Pyeongchang in February.

Saito failed an out-of-competition test for banned masking agent acetazolamide on February 4 and was withdrawn from the Games without competing.

Last week, two-time backstroke swimming world champion Junya Koga was removed from the Japanese squad for the 2018 Asian Games in Jakarta and Palembang after failing a drugs test.