Graeme McDowell has become the first golfer to be suspended under LIV Golf's anti-doping policy. However, the former major champion asserts that there is a reasonable explanation for the positive test.

LIV Golf announced on Sunday that McDowell has been suspended for one tournament and fined $125,000 after testing positive for levomethamphetamine at a tournament last month, according to Reuters.

In a statement shared on social media, McDowell explained that he had been "struggling with severe congestion" during the LIV Nashville tournament, which took place from 21-23 June. McDowell mentioned that he used a "generic Vicks nasal decongestant" to relieve his symptoms, unaware that the over-the-counter medication was listed as a banned substance by LIV.

"As a professional golfer, I understand the importance of checking all medications and the option to apply for a Therapeutic Use Exemption (TUE). Unfortunately, I did not take the time to do this due to the over-the-counter nature of this medicine, and deeply regret the oversight," McDowell wrote. "I fully accept the sanctions imposed by LIV.

"LIV’s Anti-Doping policy is designed to be thorough and transparent. Unlike some other tours, LIV enforces these rules rigorously, which made this situation particularly challenging for me. However, I respect the need for these rules and penalties — they are essential for maintaining the integrity of the sport."

McDowell, who is part of Brooks Koepka’s Smash GC team, will not be allowed to compete in The Greenbrier in White Sulphur Springs, West Virginia, next week. McDowell finished 42nd out of 54 golfers in Nashville, and Smash GC placed 12th out of 13 teams, but they have since been retroactively disqualified from that tournament.

The 45-year-old McDowell had secured four victories on the PGA Tour and 11 wins on the European Tour before signing with LIV Golf. He notably won the 2010 U.S. Open at Pebble Beach.