As expected, both players traveled with the team for a brief two-game road trip, but neither will dress for the first night of a back-to-back because of sore ankles. Garnett sat out eight games because of left ankle inflammation before playing the past two contests for Boston; Pierce has missed two games recently because of sore ankles.
The Celtics are 0-3 in the games Pierce has missed this season.
Given that Garnett and Pierce traveled to Miami, it's likely that both could be back in the lineup for Saturday's game in Orlando.
Celtics coach Doc Rivers lamented a need to rest bodies, but Boston appears resigned to settling for the seventh seed in the Eastern Conference and will rest players as much as possible.
"I don't love being in that situation, honestly, I'd love not to be, but that's the situation we're in," Rivers said after Wednesday's loss to the Nets.
Dwyane Wade, who has missed the Heat's last six games with a sore knee, plans to play against the Celtics. It's uncertain whether the Heat will have LeBron James or Chris Bosh, who both sat out Wednesday when Miami clinched the NBA's best record.