Even six-time world champion Serena Williams could not escape dating rumor mills. The 32-year-old tennis superstar, who has recently posted pictures of herself on Instagram while relaxing at the beach during a vacation in Croatia, has allegedly been dating her coach, Patrick Mourataglou.

Earlier this year, Williams had sparked speculation that her alleged romance with her long-time coach was on the rocks when she missed shots she normally wouldn't during her final doubles competition with her sister Venus Williams.

According to reports, coach Mourataglou admitted that he hadn't seen the famous athlete for two days during the said competition. He was quick to clarify, however, that he was to remain as Williams's coach and affirmed that they were well on their way to get back on track.

Rumors attributed William's less-than-stellar performance to an alleged pregnancy, but it was later on found to be false when it was announced that Serena had suffered from a viral sickness that has actually caused her lackluster performance during the said match.

Following the announcement, Williams has vowed to take a medical test necessary to make certain that she will not be playing under the same poor health condition the next time. The millionaire athlete also added that she needs additional tests just to check if her recent illness had anything to do with her genes, likely because her sister Venus suffers from Sjorgen's syndrome, an energy-reducing illness.

Presently, Williams and rumored boyfriend coach are busy preparing for the tennis star's Wimbledon comeback. Mourataglou has recently taken announcements of their Wimbledon 2014 preparations to Twitter, where he also made known his all-out support for the world champ.