Either the message hasn’t gotten through to Serena Williams or she simply doesn’t care. (Nick Laham/Getty Images)

In the case of Serena Williams and her latest on-court hissy fit in Sunday’s U.S. Open final, most would agree, the $2,000 fine she received was hardly a fitting punishment for a repeat offender on one of the sport’s biggest stages.

Credit Williams for deciding the apology should fit the fine.

Wednesday morning the 13-time Grand Slam champion tweeted a half-hearted explanation for her verbally abusive outburst.

My emotions did get the best of me this past weekend when I disagreed with the umpire. It has been a long road (cont) http://t.co/ofDWRRuWed Sep 14 11:20:17 via TwitLonger BetaSerena Williams

(continued): “to get back to the US Open this year, and I am thankful to have had such a great two weeks in New York.”

She’s also thankful to have pulled in $900,000 for finishing second at Flushing Meadows and another $500,000 for winning the U.S. Open Series. In that context, $2,000 (or 0.14 percent of her total haul) hardly registers.

Williams should be counting her blessings that Grand Slam officials decided not to hammer her with a serious fine (six figures) and suspension from a future Grand Slam event. She was still serving probation from a much-publicized threatening rant at a lineswoman at the 2009 Open. Apparently, round two was not deemed to be “a major offense.”

As such, Williams decided she didn’t need to bother with a “major apology.”