Lamont Peterson returned to the ring for the first time in more than a year and retained his IBF junior welterweight title, stopping Kendall Holt in the eighth round Friday night.
Peterson had not fought in 14 months since testing positive for synthetic testosterone, which caused the cancellation of a rematch with Amir Khan set for last May.
Peterson, who had twice knocked down Holt, caught him with a pair of right-handed blows. Peterson then landed a flurry with Holt on the ropes.
Referee Tony Weeks stopped the bout at 1:42 in the round.
Peterson improved to 31-1-1 with 16 knockouts. He defeated Khan for the IBF and WBA 140-pound titles in December 2011, also in his hometown of Washington.
The WBA stripped Peterson of its title after the positive drug test. But the IBF allowed him to keep its belt, saying an independent investigation affirmed Peterson camp's claim that the results stemmed from treatment for a medical condition.
Holt (28-6, 16 knockouts) fell to 3-4 in his last seven bouts, including 0-3 in title fights. He held the WBO 140-pound crown for about nine months in 2008-09.
Holt began the fight as the aggressor, and appeared to catch Peterson early with a quick right-handed punch.
Peterson sent Holt to the canvas for the first time with a right hook in the fourth and him backpedaling again as the round ended.
In the sixth, Peterson landed a left hook and got Holt on the ropes, before sending him down a second time with a combination.
With his right eye swelling, Holt managed to make it out of the sixth round and avoid any significant damage in the seventh, as chants of "DC! DC!" and "Pete, Pete, Pete" rose from the crowd at the D.C. Armory.
Peterson finished an obviously fatigued Holt in the eighth, sending the same crowd wild.