Sports and Twitter are a powerful combination. And often quite scary. I’m not sure what it is about the world’s fittest, but they seem to love getting themselves into hot water online – and manage to pull it off in just 140 characters.

USA Today reports that Helio Castroneves, a three-time winner of the Indianapolis 500, has been fined $30,000 for tweeting about IndyCar race director Brian Barnhart.

Castroneves wasn’t just “tweeting about” Barnhart, actually. He called him a “circus clown”, and said that he made inconsistent calls while monitoring the race.

The angry tweets came just after the televised broadcast of Castroneves’ race in Japan, where he was dropped from 7th to 22nd place after Barnhart called him out for making a pass under a yellow. Although Castroneves acknowledged his error, he claims that the 15 point drop should have just been one.

And, rather than discuss this with Barnhart or his team, Castroneves took to Twitter to vent his frustration. Along with calling the director of the race a circus clown, he also claimed that Barnhart changed the rule book whenever it was convenient for him, and that he was bringing “down an entire series.”

The $30,000 fine can be appealed, or Castroneves can pay it off by making public appearances for the series. But – for the three-time winner – the fine isn’t getting him down. He tweeted in response:

“At this point, I think it’s best to just put this situation behind me and move forward. We have a big race this weekend and my focus now is getting back on track and behind the wheel of the No. 3 Team Penske car as we try to defend our win from last season at Kentucky Speedway.”

Fines for sports stars misusing Twitter are becoming shockingly common these days. Newcastle United footballer Jose Enrique was fined £100,000 for his angry tweets directed towards the club’s owner in July, and Kobe Bryant was fined $100,000 for a gay slur, and made to apologize because of action taken by concerned tweeters.