IBF welterweight champion Errol Spence (24-0, 21 KOs) has been chasing a potential fight with Keith Thurman for some time.
Thurman (28-0, 22 KOs) has been out of the ring since last March, when he won a twelve round split decision over Danny Garca to unify the WBC, WBA welterweight titles.
After that contest, he underwent surgery for an elbow injury and remained on the shelf for the rest of the year.
He was scheduled to return in May, but withdrew with a hand injury.
A few weeks later, he was ordered to make a WBC mandatory defense against Shawn Porter - and there was another mandatory behind that, against Danny Garcia.
Instead of facing either, Thurman vacated the WBC belt - and now Porter and Garcia will battle for the vacant belt.
There is no outline for Thurman's return, but he may come back in the fall against a lower tier opponent to shake off the rust.
Spence wants to get him in the ring, but doubts the contest will happen.
"I couldn't tell you what he's doing. I think he just got married, got a kid on the way. I'm not over that one. I think he'll be back and that's a fight I definitely want. He still has one of the belts, the WBA. That's a fight I definitely want when he comes back," Spence told the Breakfast Club.
"We have the same manager, we fight on the same network. It's an easy fight to make. I don't think he's scared. I don't think he really wants the fight, because I've thrown it out there since I was 15-0. We'll see what happens."
Spence has been in action already twice in 2018, and plans to fight for a third time in the fall.
He stopped Lamont Peterson at the start of the year, and then earlier this month he demolished mandatory challenger Carlos Ocampo in one round.