After Tiger Woods picked up his 79th PGA Tour title, Lindsey Vonn gushed on Twitter that her boyfriend was the greatest of all time Credit: Dimitrios Kambouris/Getty Images

Lindsey Vonn isn't just Tiger Woods' girlfriend -- she's also his biggest fan. After Woods won his 79th PGA Tour title at the World Golf Championships-Bridgestone Invitational on Sunday, Aug. 4, the skier took to Twitter to gush about her main man.

"So proud!!!!" she wrote of his victory, along with the number 79 and the hashtag "#GOAT," which is an acronym for "Greatest Of All Time."

Vonn, 28, has been a steady presence at Woods' tournaments in recent months. And though she was reluctant at first to even acknowledge their relationship, she's been increasingly open about her personal life ever since the two went public in March.

"Tiger's fame is obviously in the extreme, the amount of scrutiny that he's constantly under," she told Vogue in a July interview. "But that's the thing: It all comes back to being happy. It doesn't really matter what anyone else thinks; do what you love to do and be happy and that's it."

"It's amazing," she said when asked about dating the scandal-plagued golfer, 37, whom she met at a charity event in 2012. "Life changes very quickly, in a very positive way, if you let it."