Carl Frampton recovered from being knocked down twice in the opening round to retain his IBF super-bantamweight title with a unanimous points decision over Alejandro Gonzalez Jr in El Paso.
Frampton, 28, was forced to drop to his knee twice but gradually gained control over his dangerous Mexican opponent.
Two judges scored the fight 116-108 in the Belfast fighter's favour, with the other awarding him the contest 115-109.
Gonzalez was twice deducted a point for persistent low punches.
Making his first appearance on American soil and defending his crown for the second time, Frampton found himself on the canvas for the first time in his professional career after taking a left hook on the chin from the gritty and determined 22-year-old.
A standing eight count followed and the under-par champion was then rocked by a straight right hand before the end of a dramatic first round.
The unbeaten Northern Irishman recovered from his very unconvincing start to put pressure on Gonzalez in the second, delivering some good combinations.
The challenger, ranked 13 by the IBF, lost a point for low punching in the third, having twice been warned by the referee.
Gonzalez was providing a much sterner test than anticipated but Frampton began to dominate the middle rounds of the bout, improving his defence and delivering the more effective punches.
The ninth and 10th rounds saw something of a revival from Gonzalez, but he suffered a further setback with the loss of a second point for low blows in the 11th.
After the fight, Frampton told ITV Sport that he was "disappointed with his display".
He added: "I have to give Alejandro Gonzalez so much credit. It's not the performance I wanted but he can punch, he's a warrior.
"I was in shock a bit after the first round as I had never been knocked over before, but I recovered well from the two flash knockdowns.
"I got the win and delivered plenty of excitement, but I didn't manage the knockout. Two out of three ain't bad."
Now unbeaten in 21 fights in the professional ranks, Frampton went on to admit that he had difficulty making the weight for the contest and may consider a move up to the featherweight division.
"I have to seriously consider whether to stay at this weight or go to featherweight. I had a lot of weight to take off during the last few days before the fight."