"Danny Garcia stepped up and said, 'I want to be the one who beats this guy,' " Ellerbe said.
The fight was added Thursday to the undercard of boxing's biggest fight of the year: Floyd Mayweather vs. Canelo Alvarez.
Garcia, 25, will need to use his speed and ability to fight with both hands to counter Matthysse's strong right. In April, Garcia displayed his growth as a complete fighter when he defended against a desperate Zab Judah en route to a gritty unanimous decision.
"Matthysse is a good fighter and has a big punch," Garcia said. "But I'm a talented fighter with what it takes to be a champion and stay that way."
A win against Matthysse could line up Garcia (26-0, 16 KOs) to meet Mayweather next spring.
Garcia's last fight in Vegas was last July, when he stunned Amir Khan with a fourth-round knockout to post the signature win of his career.
Two months ago, Garcia sat in the front row at Atlantic City's Boardwalk Hall and watched Matthysse dismantle Lamont Peterson en route to a third-round TKO. Matthysse (34-2, 32 KOs) has won six straight by stoppage after dropping a split decision to Devon Alexander in June 2011.
Hopkins fight set. Forty-eight-year-old Bernard Hopkins (53-6-2, 32 KOs) will defend his IBF light-heavyweight title against Karo Murat (25-1-1, 15 KOs) on Oct. 19 at Atlantic City's Boardwalk Hall. The fight was originally scheduled for July 13 in Brooklyn, but Murat, the mandatory challenger, had issues obtaining a visa.
Contact Matt Breen at firstname.lastname@example.org and follow @matt_breen on Twitter.