Former tennis star Serena Williams could not pass up an opportunity to speak about on-court nemesis Simona Halep's four-year ban from the sport after being found guilty of doping violations.

The 23-time Grand Slam winner posted a cryptic hint on social media platform X, formerly Twitter, which seemingly referred to her Romanian rival.

"8 is a better number," Williams wrote.

Halep notably denied Williams an eighth Wimbledon title after the former came out on top of their championship match in the 2019 edition of the tournament.

While the 41-year-old retired athlete neither confirmed nor denied the tweet's reference, it likely means she wants to be awarded her eighth Wimbledon championship.

Simona Halep handed four-year ban from tennis

The Romanian tennis star is barred from competing in professional tennis for the next four years after committing "intentional" anti-doping violations.

Halep failed a drug test during the 2022 US Open, testing positive for roxadustat, a drug that treats anemia but is considered a blood doping agent because it increases hemoglobin and the production of red blood cells.

In addition, according to the International Tennis Integrity Agency, there were irregularities found in her Athlete Biological Passport, an individual electronic record for professional athletes listing their doping tests.

The two-time Grand Slam winner will be eligible to compete again in October 2026, when she will be 35 years old.

Halep won the 2018 French Open and 2019 Wimbledon, and she was the WTA's year-end No. 1 in 2017 and 2018.