Filipino-American fighter Nonito Donaire has joined Belfast's Ryan Burnett in the bantamweight edition of the World Boxing Super Series.
The decorated 35-year-old lost to Burnett's compatriot Carl Frampton at featherweight in April but has previously proved a more natural fit at 118lbs.
Donaire becomes the fourth addition to a competition that will eventually feature eight fighters.
Burnett is the WBA champion, and Emmanuel Rodriguez and Zolani Tete respectively hold the IBF and WBO titles. Japan's highly rated Naoya Inoue is also expected to be one of the eight.
"I believe my size, experience and most of all my power will give me the edge over my opponents," said Donaire.