WASHINGTON – Karen Chukhadzhian took a lot of criticism once he agreed to fight Jaron Ennis on Saturday.

The unknown Ukrainian contender didn’t remotely come close to pulling off what would’ve been an enormous upset, but the previously unproven welterweight became the first foe to take Ennis 12 rounds during his six-year pro career. Even with all of his obvious advantages, Ennis only sporadically landed flush punches on the reluctant Chukhadzhian, who showed some defensive skill while losing a lopsided 12-round unanimous decision on the Gervonta Davis-Hector Luis Garcia undercard at Captial One Arena.

While it was far from his most impressive performance, judges David Braslow, Tammye Jenkins and Paul Wallace all scored it a shutout for Ennis. Philadelphia’s Ennis won 120-108 on each scorecard and captured the IBF interim welterweight title.

The faster, stronger Ennis ended Chukhadzhian’s 20-bout winning streak, but Chukhadzhian (21-2, 11 KOs) became the first fighter to extend Ennis beyond the sixth round.

The 25-year-old Ennis (30-0, 27 KOs, 1 NC), who went off as a whopping 35-1 favorite, also moved closer toward securing a shot at the IBF welterweight title owned by unbeaten Errol Spence Jr.

The 32-year-old Spence (28-0, 22 KOs), of DeSoto, Texas, hasn’t expressed genuine interest in facing Ennis. Spence could move up to the 154-pound division if the IBF tries to force him to defend one of his three welterweight titles against Ennis.

It became painfully apparent to the bored crowd by the 12th round that Chukhadzhian would take Ennis the distance. Ennis pressed the action again in the final round, but he couldn’t catch Chukhadzhian with the type of shot that could’ve ended their bout.

Ennis blasted Chukhadzhian with a right hook in the 11th round. Chukhadzhian covered up thereafter, though, and didn’t allow Ennis to land another hard shot in that sequence.

A right hook by Ennis turned Chukhadzhian’s head around just before the halfway point of the 10th round. Ennis attacked Chukhadzhian’s body later in the 10th round, which made him move even more than he did during the first nine-plus rounds.

Ennis hit Chukhadzhian with multiple punches during the ninth round that caused Chukhadzhian to tie him up.

The restless crowd, anxious to see Davis fight, began booing during the eighth round, when Chukhadzhian again remained out of Ennis’ punching range and defended himself well.

Ennis’ right hook landed about 1:15 into the seventh round. A right-left combination by Chukhadzhian landed about 30 seconds later.

Ennis snapped back Chukhadzhian’s head with a right hand 55 seconds into the fifth round. Ennis later snuck in a left hand just before the fifth round concluded.

Ennis drilled Chukhadzhian with a right hand that made him retreat in the fourth round.

Ennis caught Chukhadzhian with a couple left hands during the third round, but again found it troublesome to land with regularity against his defensive-minded opponent. A straight left by Ennis forced Chukhadzhian to hold him just before the third round ende.

Chukhadzhian kept his distance and remained on his back foot for most of the second round. Ennis couldn’t connect with flush punches in that round in part because Chukhadzhian wasn’t willing to engage.

Ennis knocked Chukhadzhian off balance with a jab 40 seconds into their fight. Chukhadzhian mostly moved around the ring and avoided Ennis’ hardest shots for the rest of the opening round.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.