"The urgency and also the basketball IQ and disposition, everything, just went to a whole 'nother level," Clippers forward Caron Butler said.
For the Heat, the flu has been a bit of an issue of late.
Heat President Pat Riley missed the team's recent visit to the White House because of the illness, and Bosh has been fighting it for much of this week. Allen was not at the shootaround, and it was clear then that he wouldn't be available for the Clippers game.
Miami next plays on Sunday, home again against the Los Angeles Lakers.
"I feel different each day," said Heat forward LeBron James, who has battled congestion this week. "Just try to get as much Vitamin C, just try to take your vitamins, just try to stay on course and not let it affect you."
Heat coach Erik Spoelstra said he wasn't caught off guard by the Clippers having their full roster back, and that Miami prepared for that likelihood.
There was one roster move the Heat made on Friday that wasn't illness-related: They signed forward-center Chris Andersen for the remainder of the season, as has been expected since they brought him into the organization three weeks ago.