Shawn Porter retained his World Boxing Council welterweight title on Saturday with a split-decision victory over Cuban challenger Yordenis Ugas.
Two judges awarded the fight to Porter by scores of 116-112 and 115-113 while the third saw Ugas a 117-111 winner.
"I was on my toes all night," said Porter. "I was very focused the entire fight and just listening to my corner. We wanted to out box him and eventually turn it on and press him. But my dad did not think that was the smartest way to win the fight. We fought this way for 12 rounds and no one has ever seen that from me before."
But Porter, who searched in vain for his first knockout in two years, was far from overpowering after needing an extra two hours Friday at the weigh-in to drop within the 147-pound (66.7kg) division limit.
Ugas, who took a bronze medal at the 2008 Beijing Olympics, fell to 23-4 and saw his eight-fight win streak snapped despite going 12 rounds for only the second time in his career.
"We fought a good smart fight tonight," said Porter. "I was consistent and I thought we won a majority of the rounds. We got the win, we're still champion and we're looking forward to what is next."
Porter was aggressive in attacking the larger Ugas in the early rounds but the defiant challenger began working to Porter's body, mindful of weigh-in struggles, and taunted the champion to engage more, hoping to take full advantage of his reach edge.
Ugas and Porter traded punches in the middle rounds, with the American using speed and timing to keep Ugas off-balance but the Cuban answering every punch when Porter moved inside.
Porter landed a solid left jab at the end of the 11th round to wobble Ugas, setting up an intense final round.
Porter went down in a corner after a swinging right by Ugas but referee Jack Reiss ruled it a slip and the rivals exchanged punches to the last bell.