At 49, Bernard Hopkins has cemented his place in boxing history while making millions. So why does he continue to fight? The Post's Gabe Silverman rides with Hopkins back to the Philadelphia projects where he grew up to try and figure out the answer. (Gabe Silverman/The Washington Post)

Using technical expertise, guile and a healthy dose of showmanship, IBF 175-pound champion Bernard Hopkins, 49, became the oldest fighter to unify major world titles by beating Beibut Shumenov via split decision. With the victory, Hopkins earned Shumenov’s WBA belt as Saturday night moved into Sunday morning at the D.C. Armory.

Already the oldest athlete to own a world championship, Hopkins (55-6-2, 32 knockouts) added to his legacy with a second straight defense of his light-heavyweight title against his Kazakhstani opponent, who is 19 years his junior. Hopkins did the most damage in the 11th round when he caught the 2004 Olympian with a straight right that sent Shumenov (14-2, 9 KOs) to the mat.

“One thing I just want to know before I leave this game, that I gave it my all. I gave it my all. Let me tell you, the best pound-for-pound fighter in the world right now is Floyd ‘Money’ Mayweather. I tell you, behind Andre Ward, who I believe is second and should be, I ain’t far from the top three I feel because of my age and the way I’m doing it. I’m not fighting cream puffs. I’m just telling you I’m not done yet.”

The majority of the announced 6,823 began chanting Hopkins’s name in the aftermath of that knockdown, and the only suspense in the final round was whether Hopkins would be able to record his first knockout since 2004. Even though he was unable to accomplish that feat, Hopkins continued to cement his place in boxing history.

There was a smattering of boos when ring announcer Jimmy Lennon Jr. revealed two judges awarded the decision to Hopkins, 116-111, and a third to Shumenov, 114-113.

“I’m special,” Hopkins told Showtime after the fight when asked how he was able to win despite his age.

The fight began with both fighters sizing up one another in Round 1, creating a round bereft of much activity from either side. Shumenov, 30, was a bit more energetic in the second, sporadically landing shots while Hopkins continued to measure his far less experienced opponent.

But Hopkins sped up the pace in Round 3 and landed several jabs that brought the crowd to life momentarily. In one sequence, Shumenov looked at the referee Earl Brown for a split second, and Hopkins quickly moved in with a right cross that connected cleanly.

Shumenov “can fight, gave me some awkward problems, but I never wavered. Let me tell you, I didn’t underestimate him as you see in this 12-round performance. I tried to stop him. He's tough,” Hopkins said.

The first indication Hopkins was hitting his stride came when he stuck out his tongue in Round 4 while in the corner. With Shumenov trying to keep him there, Hopkins moved out of harm’s way and began to land shots thereafter with much more regularity.

In the sixth round, Hopkins struck with a straight left that sent Shumenov’s head flinging backward. Excited fans out rose out of their seats immediately after that blow, and Hopkins drew even more applause when he waved his right arm around as if to announce more was on the way.

Hopkins’s command of the ring escalated as the fight moved into the later rounds. Each time Shumenov left even the slightest opening, Hopkins was able to land shots and do damage, leading to the knockdown that all but settled the outcome shortly after midnight.

“Obviously I chose the wrong strategy,” Shumenov said. “I’m still a warrior.​”

Hopkins has fought in or around the District four times since turning professional in 1988. In his first try at claiming the IBF middleweight title, Hopkins lost to Roy Jones Jr. via unanimous decision in 1993 as part of the undercard of then-heavyweight world champion Riddick Bowe’s victory over Jesse Ferguson at RFK Stadium, steps from where Hopkins fought this time.

Hopkins beat Segundo Mercado to claim the belt in 1995 at what was then US Air Arena in Landover and defended the title twice in the area. The first came against Andrew Council in 1997 in Upper Marlboro, and Hopkins beat Robert Allen two years later at the Walter E. Washington Convention Center.

The co-main event featured IBF welterweight champion Shawn Porter punishing Paulie Malignaggi in the opening rounds and ending the proceedings with a violent flurry that had the former two-time and two-division world champion on the ropes in the fourth.

Porter’s left hook followed by a combination left Malignaggi all but helpless, prompting referee Sam Williams to stop the fight at 1 minute 14 seconds. Porter (24-0-1, 14 KOs) remained undefeated after his first title defense since winning the belt via unanimous decision over Devon Alexander in December 2013.

In the first televised undercard bout, World Boxing Organization middleweight champion Peter Quillin mixed his jab and repeated uppercuts to complete a thorough if not necessarily entertaining victory over Czech Republic challenger Lukas Konecny.

As a reigning undefeated champion in the division where Hopkins ruled in his younger years, Quillin (31-0, 22 KOs) simply outworked his opponent, who was fighting in the United States for the first time. Quillin, 30, landed shots virtually at will, opening a cut above Konecny’s eye and leaving his face red from absorbing blow after blow.

The early portion of the undercard included a handful of area fighters, including the professional debut of Upper Marlboro lightweight Lamont Roach Jr. The freshman at Maryland beat Victor Galindo by unanimous decision in their four-round bout that immediately preceded Quillin-Konecny. All three judges awarded every round to last year’s Golden Gloves and U.S. amateur champion.