Argentina's Marcos Maidana took Adrien Broner's WBA welterweight crown on Saturday night, twice knocking down his man as he inflicted a first career defeat on the American.
Maidana eventually claimed a unanimous decision in San Antonio's Alamodome with the three judges scoring the contest 115-110, 116-109 and 117-109 in his favour.
Broner had entered the contest as a red-hot favourite, but big-hitting Maidana was the aggressor from the off and staggered his rival with an overhand right in the first.
Broner did not heed the warning and was put down for the first time in his career in the second as he went crashing into the ropes, although he beat the count and smothered Maidana to make it through to the bell.
The 24-year-old American then appeared to regain his composure somewhat and began to work his way back into the contest over the next few rounds, landing with some clean shots of his own.
Indeed, Broner looked to be getting on top after producing some of his best work in rounds five and six, although Maidana was still unleashing as and when the opportunity arose.
But having got a foothold, Broner was then stunned by another vicious Maidana assault in the eighth, a combination of punches to the head and body putting the champion down for a second time.
Once again he was up in time to continue and he was given some respite when Maidana was subsequently deducted a point for the use of his head later in the round.
However, the Argentine was very much on the front foot and would go on to visibly hurt his man in both the ninth and tenth as he all but wrapped up the contest.
Broner did well to survive and showed real courage as he went after his man in the last to try and secure a knockout that he clearly needed, but Maidana did well to keep him at bay and deservedly picked up a convincing decision.
A distraught Broner (27-1-0) quickly left the ring after the scores were announced and will have plenty to ponder having suffered such a surprising and one-sided defeat.
For Maidana (35-3-0), whose three career defeats have all come on points against Andriy Kotelnik, Amir Khan and Devon Alexander, it is a second world title in a second weight division.
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