It brings new meaning to kiss and tell.

In March, Gil Roberts, who will compete for the U.S. in the 400 meters at the world championships in August, tested positive for an illegal diuretic and masking agent during an out-of-competition test by the U.S. Anti-Doping Agency. On Thursday, officials announced he won’t receive a violation because, as it turns out, the low level of probenecid in his system likely came from smooching with his girlfriend.

According to the decision released by USADA, Roberts, 28, who was a member of the 4 x 400-meter relay team that won gold in Rio last year and has never before tested positive for performance-enhancing drugs, kissed his girlfriend “frequently and passionately” after her return from a trip to India. While visiting India, she came down with a sinus infection and received medication from a local “chemist.” She continued to take the medication upon her return to the U.S., including on the day that Roberts was tested at his home. Because she couldn’t swallow pills, she emptied the substance from a capsule into her mouth.

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“…Roberts had dated [his girlfriend] for two years and surely had kissed her before without being charged with a doping violation,” the arbitrator wrote in the decision. “Thus, for Roberts it must have been like lightning out of the clear blue sky for him to learn that by kissing his girlfriend this time that he was exposing himself to a prohibited substance. Roberts has met his burden of proof.”

A message to Robertss agent was not immediately returned. The full report is available here.

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Probenecid is on the banned substance list because it can stop the detection of other performance-enhancing drugs, like steroids.

Roberts’s case is one of a couple unusual ones to come before USADA. Last month Ajee’ Wilson was also cleared of wrongdoing after it was concluded that an illegal substance in her test was the result of consuming meat tainted with zeranol, a growth hormone legally used in U.S. beef cattle. Wilson is also headed to the world championships next month in London to compete in the 800 meters.

As for Roberts, USADA said he is at no fault and will not receive any suspension or disqualification of results.

preview for 2016 Olympic Track Trials: Men's 400: Gil Roberts

Roberts speaks to the media after the 2016 U.S. Olympic Trials.