LAUSANNE, Switzerland (AP) — World champion sprinter Salwa Eid Naser was banned for two years and will miss the Tokyo Olympics after sport’s highest court on Wednesday overturned a ruling that had cleared her on a technicality for doping tests she missed.

The Court of Arbitration for Sport (CAS) reversed an independent tribunal’s October 2020 decision that at the time cleared the Bahraini 400-metre runner to compete in the Tokyo Games.

“Salwa Eid Naser is sanctioned with a period of ineligibility of two years, commencing on 30 June 2021,” CAS said in a statement Wednesday.

The ban will end in early 2023 as Naser will get credit for just over four months “for the period of provisional suspension already served” between June and October 2020, CAS said.

The 23-year-old Naser, who was born in Nigeria but competes for Bahrain, ran the fastest women’s 400 since 1985 to win the world title in 2019 in Doha, Qatar.

The World Athletics Disciplinary Tribunal had ruled in October 2020 that Naser had not committed an anti-doping violation related to a filing failure and missed tests between March 2019 and January 2020.

The tribunal’s ruling had been based on a technicality — counting back the date of a rule violation to take effect from the start of a three-month period.

The World Anti-Doping Agency (WADA) and World Athletics both filed appeals at CAS to challenge the tribunal’s ruling, leading to the reversal on Wednesday.

Naser had been charged by the Athletics Integrity Unit for at least three “whereabouts failures” within a 12-month period, which can lead to a two-year ban.

Athletes must give updates on a WADA online platform where they can be found for no-notice testing outside of competition. A violation means an athlete gave wrong information or was not where they said they would be when sample collectors arrived.

Naser’s three proven whereabouts failures happened within a 12-month calendar period but were spread out over more than one year.

Although Naser failed to file accurate information to give a sample on March 16, 2019, it technically was counted as happening at the start of the quarter on January 1, 2019. Her proven missed tests were on March 12, 2019, and January 24, 2020 — making the combined time span longer than one year.

But CAS overturned that finding and found Naser “guilty of a violation of Article 2.4 of the IAAF Anti-Doping Rules.”

It did not strip Naser of her 2019 World Championship result.