"We have dismissed Danielle Collins...for the remainder of the 2020 World TeamTennis season after breaking our Covid-19 protocols and leaving The Greenbrier Resort and the state of West Virginia," WTT Chief Executive Carlos Silva said in a statement.
"The protocols have been put in place and communicated numerous times to protect the health and safety of our players, coaches and staff which are of utmost importance to WTT."
The organisers did not provide details about the travel undertaken by the 26-year-old Collins, who made the semi-finals of the 2019 Australian Open, and revealed a diagnosis of rheumatoid arthritis at the end of last year.
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Collins last month criticised Novak Djokovic after the men's world number one said it would be "impossible" to play this year's US Open under Covid-19 protocols proposed by organisers.
She wrote then on Instagram: "It’s easy when someone’s made $150 million throughout their career to try and tell people what to do with their money, and then turn down playing in the US Open.
"For those of us (most tennis players) who don’t travel with an entourage, we actually need to start working again. It would be nice to have the best player in the world supporting this opportunity and not spoiling it for the players and the fans!”
After that tournament, she reached a career-high ranking of world number 23, and currently sits just outside the top 50.
One of only a few live sports events allowing fans in North America to attend amid the novel coronavirus pandemic - albeit a limited number of fans, permitting only a fifth of the stadium capacity - the entire three-week regular season of the mixed-gender competition is being held at the Greenbrier resort in West Virginia, and features multiple Slam winners Venus Williams and Kim Clijsters.
Safety measures taken by WTT to curb the potential spread of the virus include swab testing for participants and regular temperature checks within the tournament bubble.
Frances Tiafoe, who reached the quarter-finals at the 2019 Australian Open, was forced to drop out of the WTT events after testing positive for Covid-19 while playing at the All-American Team Cup exhibition tournament in Atlanta.
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