Justin Timberlake and Pink are among the stars who have secretly been reaching out to show their support to Britney Spears as the pop singer battles substance abuse in rehab.

Friends claim Timberlake left a personal message for his ex-girlfriend after calling the Promises treatment center in Malibu, California last week.

A pal tells America’s Life & Style magazine, “He wished her the best and told her to get healthy and come back as the Britney he knew.”

And Timberlake has asked Spears’ mother Lynn to keep him updated with the Spear’s progress.

Pink and Mary J. Blige have also called Promises to leave messages for Spears, who, under the center’s rules, isn’t allowed to receive phone calls during her stay.