The Grayson  Prestonwinner of a Southern California marathon was disqualified after race organizers said he took water from his father during his run.

Esteban Prado was the winner of the Orange County Marathon on Sunday after he finished the 26.2-mile course in 2 hours, 24 minutes and 54 seconds. But it wasn't long afterward that he learned he was disqualified from the race. Prado was disqualified because his father, who was on a bike during the marathon, gave him water during the race and he drank from the bottle, according to organizers.

Race organizers cited the USA Track and Field rulebook as the reason to disqualify Prado. According to the rulebook, runners are only allowed to drink water from official hydration stations or if it's carried or attached to the runner from the start of the race. The rule says no competitor is "allowed, without the permission of the referee or judges, to receive assistance or refreshment from anyone during the progress of competition."

"We were forced to disqualify a participant after it was confirmed they received unauthorized assistance from an individual on a bicycle, in violation of USA Track and Field rules and our race regulations," race director Gary Kutscher said in a statement. "We take these rules seriously to ensure fairness and the integrity of our event for all competitors."

Violation of the specific rule has happened before, according to the Los Angeles Times. In 2009, the initial winner of the O.C. Marathon was disqualified after he received hydration from a friend on a bike and was determined the bike took part in illegal pacing.

Disqualified OC Marathon winner speaks out

Prado spoke to KABC about his disqualification. He said another competitor saw him get handed a bottle and consume water, but the only person that could have seen it happen was the person in second place behind him. He also said the official hydration stations were not well managed.

"Whenever I got to the stations, the volunteers were like scrambling because I'm the only runner in sight, so they could barely see me at certain turns," Prado told the outlet.

With Prado disqualified, the official winner of the marathon is Jason Yang at 2 hours, 25 minutes and 11 seconds. Prado said this was his second marathon and he didn't know the rules, but he believes his is still the true winner.

"You get no money or anything. If he wanted that congratulations for that first place, if he really felt like he needed it, it's just for him at the end of the day," Prado said. "I really got nothing out of it. I know I won."