The singing star, who has battled lupus, said it got to the point where it was "kind of life or death".
Gomez revealed she had received a transplant on September 14 by sharing a photograph on Instagram of her and Francia lying side-by-side in their hospital beds holding hands. "That was it and I didn't want to ask a single person in my life ... and she volunteered and did it".
"You feel Francia saved your life?"
Gomez told TODAY that she was reluctant to seek a donor after learning she needed a transplant to save her life. The Today show announced on Friday, October 27, that the segment will air next Monday.
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The 25-year-old pop singer underwent the transplant earlier this year due to Lupus.
"There aren't words to describe how I can possibly thank my attractive friend Francia Raisa", Gomez wrote in the post. I am incredibly blessed.
"I obviously love her so much and want her to do what she does and she's killing it", Selena told Zane Lowe during an Apple Music interview.
Raisa, who is an actress herself, spoke humbly of her generous gesture in her own social media posts last month. The actress also took to Instagram after Gomez dropped the news saying she was "beyond grateful" God trusted her to save her friend's life - and changed hers in the process.
Gomez has since bounced back to health.