The All My Children star will play a love interest for Bree (Marcia Cross) in the show's final season, according to ABC Soaps In Depth.
"I play one of Bree's lovers," the actor confirmed. "We have a couple of fun scenes. I really loved working with her. She is very kind and generous."
Mathison played Ryan Lavery on All My Children from 1998 until the show's cancellation earlier this year.
He has also appeared in episodes of CSI, JAG and a special soap-themed instalment of Castle.
ABC confirmed in August that the current eighth season of Desperate Housewives will be the show's last.
The series airs on Sunday at 9/8c on ABC. Mathison's appearance is expected to air in late January.
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