Major League Baseball's Philadelphia Phillies have closed their Florida training base after eight Covid-19 positives and the Toronto Blue Jays, San Francisco Giants and the NHL's Tampa Bay Lightning also shuttered training facilities.
Friday's moves came as state officials announced a record one-day spike of Covid-19 cases, with nearly 4 000 new record infections in Florida.
The NBA and Major League Soccer plan to gather in quarantine areas near Orlando to resume their virus-halted campaigns in July after play was stopped in March.
The Phillies said five players and three staff members tested positive for Covid-19 at the club's Clearwater training facility, which MLB said was being shuttered indefinitely.
The team said a further 12 staff members and 20 players from the club's major league and minor league rosters were awaiting results of tests.
The Tampa Bay Times and ESPN reported the NHL Lightning closed its training facility, just 23 miles (37 kilometres) from Clearwater, after multiple players and staff members tested positive for Covid-19.
The Lightning facility is closed until at least 6 July, the Times reported.
The Blue Jays closed their spring training facility in Dunedin, four miles north of Clearwater, after a player exhibited coronavirus symptoms, ESPN reported, saying the player had recently spent time with Phillies players. He is awaiting results of a Covid-19 test.
Phillies managing partner John Middleton said all the team's facilities were being closed as a precaution.
Owners stick to 60 games
"The Phillies are committed to the health and welfare of our players, coaches and staff as our highest priority, and as a result of these confirmed tests, all facilities in Clearwater have been closed indefinitely to all players, coaches and staff and will remain closed until medical authorities are confident that the virus is under control and our facilities are disinfected," Middleton said in a statement.
The club said it was "too early to know" how the Clearwater outbreak could impact the Phillies' 2020 season.
The San Francisco Giants also shut their facility in Scottsdale, Arizona Friday after one person and a family member exhibited symptoms on Thursday.
Major League Baseball is currently locked in bitter negotiations with the league's players union over the terms of a shortened season. The back-and-forth negotiations continued Friday with the owners reiterating they are sticking to a planned 60-game schedule. The players want that increased to 70 games.
Also on Friday, Toronto Maple Leafs star Auston Matthews went into quarantine at his home in Arizona after testing positive for Covid-19, the Toronto Sun reported.
The 22-year-old Matthews is hoping to be healthy enough to attend the Leafs' training camp which begins on 10 July. Arizona, especially the Phoenix area where Matthews grew up, has also seen a spike in cases.
The Leafs released a statement Friday but declined to confirm or deny.
"The Toronto Maple Leafs will not be commenting on reports surrounding testing for any of the Club's players or staff.
"The league will provide updates on a regular basis with aggregate totals of the number of tests conducted and number of positive tests reported without disclosing either the identities of the affected Clubs or Players," the team spokesman said.
The NHL said in a separate news release that since training facilities re-opened on 8 June, 11 players have tested positive for Covid-19.