The 26-year-old hasn't been with the club since leaving the bubble on July 17, and head coach Doc Rivers wants him to take all the time he needs.
"From others, I get asked from inside like, when is Trez coming back, and my answer's been the same. When he's ready, he'll come back," Rivers told reporters Saturday, according to ESPN's Ohm Youngmisuk. "You can't play if you're not right mentally and because of the emotional part of it. ... His grandmother is very tight with him, so all I told him is I love him and take your time. We'll be ready with open arms when you come."
Rivers has been very outspoken in support of his players. Veteran Lou Williams returned to his native Georgia to attend a funeral while guard Patrick Beverley also left Orlando for an urgent family matter.
The Clippers bench boss says he's given players a day off in the past to take care of personal issues and wants to raise awareness across the NBA toward mental health.
"I think it's the untapped resource in our league," Rivers said. "Not only just players but coaches, too. I don't know why it's always been taboo, but it has been, and we have to do a better job of making it like a sprained ankle where you get treatment just like you do if you injured your knee or something like that.
"I mean, we had three major things happening to our guys, and my job then is just forget the coaching part, just to support. We have several therapists on staff, the league has a therapist here full-time, and we should all seek it out. It shouldn't be something that we resist."
Harrell is among the leading contenders for the NBA's Sixth Man of the Year award. He's averaging 18.6 points and 7.1 boards in 27.8 minutes per contest.