After his 12th-round stoppage victory over Albert Bell to retain his WBO lightweight title on Saturday at Wolstein Center in Cleveland, Mason said he’s open to a unification bout in his next fight.

“I'm very interested,” Mason said on the latest episode of Inside The Ring, which aired on DAZN on Monday. “In boxing, you’ve got to prove that you’re the best in the sport, so that's what I'm open to doing. I'm open to proving that, and whoever I step in the ring with, I'm definitely open to making it happen.”

The lightweight division will be at the forefront Aug. 1 when William Zepeda faces Lamont Roach for the vacant WBC title at Virgin Hotels in Las Vegas as part of “The Fight” series, which airs on DAZN and TNT. In the co-feature, IBF titleholder Raymond Muratalla faces former junior lightweight champion Robson Conceicao.

Muratalla (24-0, 17 KOs) is The Ring’s No. 2 lightweight, while Zepeda (33-1, 27 KOs) is No. 3. Roach (25-1-3, 10 KOs) held the WBA junior lightweight title before fighting at lightweight and junior welterweight in majority draws against Gervonta “Tank” Davis and Isaac Cruz in his last two fights.

“I'm open to stepping in the ring with any of those fighters,” Mason said. “I wish them the best, and hopefully they come out healthy, and whoever's next for me, let's get it.”

Mason (21-0, 18 KOs), who moved up to No. 4 in The Ring’s lightweight rankings released Monday, had to overcome dicey moments in the first half against Bell (28-1, 9 KOs). Bell, 33, outboxed the Cleveland-based southpaw in the first half and led 58-56 on one judge’s scorecard, while the other two had it knotted at 57-57.

Mason, 22, seized control in the seventh round by landing his left hand and digging the body. Mason believed he had done enough to be ahead heading into the final round, and he led 107-102 twice and 106-103 across the three judges’ scorecards, but his father and brothers pressed him to pursue the finish.

He ultimately took it out of the judges’ hands, dropping Bell twice as referee Mark Nelson stopped the fight after the second knockdown without a count.

“Going into the 12th, I was up in the fight, and I felt pretty comfortable knowing that I did what I had to do,” Mason said. “I was touching that body, stabbing him, and that's how I wanted to fight to go. I definitely wanted to break him down before anything, but my brother was like, ‘Yo, go ahead, get him on,’ and I'm like, "OK, man, let me flip that switch and turn it up a notch and go ahead and get the stoppage.’”