Serena Williams has taken to social media following the news of Simona Halep's four-year doping ban to throw shade at her former rival.

The International Tennis Integrity Agency (ITIA) announced today that former World No. 1 Halep would be banned from the sport for four years due to doping violations.

The Romanian player was suspended provisionally last October after she tested positive for the banned substance roxadustat at the 2022 US Open. In May of this year, she was hit with a second doping charge, citing irregularities in her biological passport.

Halep has repeatedly expressed her frustration at the delays in the case, but now she has heard the news that she didn't want to hear. After the verdict was revealed, Halep confirmed that she would be appealing the decision and expressed her shock and disappointment.

However, one player who seems to have no sympathy for Halep is 23-time Grand Slam champion and tennis legend Serena Williams. The American player shared her thoughts via a brief but loaded post on X, formerly known as Twitter.

"8 is a better number," she wrote.

While the tweet does not explicitly reference Halep, fans quickly put the pieces together and realized Williams was suggesting that the two-time major champion should be banned for eight years rather than four.

Moreover, the number 8 has a specific association with the 2019 Wimbledon final, where Williams lost to Halep in straight sets. If the result had gone the other way, the now 41-year-old would have won her eighth title at the All England Club.

This would have also been her 24th major singles title - a goal that Williams aimed toward for a while but ultimately did not achieve before she retired in September 2022.

Players and fans alike have had a mixed reaction to all of the developments going on in the case. While Williams and others such as Eugenie Bouchard have taken subtle digs at Halep, others such as Williams' former coach Patrick Mouratoglou have instead defended the 31-year-old.