Johnny Nelson reigned over the 200-pound division for six years and 13 title defenses from 1999 to 2005.
Marco Huck had matched him on both counts, with 13 defenses of his own and a six-year run from 2009-15.
But he was looking to take those records all for himself August 14 with a win over Polish southpaw Krzysztof Glowacki.
The fight in Newark, New Jersey, was Huck's first in America in his 11-year career.
All but two of his other bouts came in Germany, where he lorded over the championship he took from Victor Emilio Ramirez.
Like Huck, Glowacki had never fought outside of Europe.
Two years Huck's junior, the 29-year-old Glowacki had built up a 24-0 record in his native Poland.
The challenger jumped out as the aggressor, landing a right hook that staggered Huck late in Round 1.
Glowacki swept the first three rounds on two of the three judges' scorecards and two of three rounds on the other.
The champ stepped it up and took over in the fourth, landing a series of nasty counter rights.
In the sixth, he floored Glowacki with a winging, overhand left.
Glowacki's legs knew it before his head did, as he first wobbled, then slowly sat, then fell flat on his back–the first time he'd hit the canvas in his career.
For a guy who didn't get to his feet until the count of nine, though, what came next was stunning.
As soon as the action resumed, Glowacki–despite admitting later he had no idea where he was–unloaded on Huck in a wild attack.
The champ had to be wondering if it was going to take a tranquilizer dart to stop his Polish foe.
Huck held Glowacki off through the end of that round, and then for the next four.
But the 11th would tell a different story.
Whether he realized it or not, Glowacki was behind in the fight, too far behind at that point to win a decision.
The cards through 10 were 95-94 on one, but an insurmountable 96-93 on the other two.
Huck's knockdown in the sixth was the difference-maker, and from there he continued picking Glowacki apart with counter rights.
With a minute left in the 11th round, Huck shoots a five-punch flurry to Glowacki's head.
He follows with a double jab and a big right. Glowacki ducks it but doesn't return fire.
Huck throws a left hook and follows it with a straight right, but he doesn't bring his hands back.
This is the window Glowacki is looking for.
He spins a left of his own over Huck's right arm and opens the door for a straight right that lands flush.
Huck goes down. He beats the count and is barely back on his feet when Glowacki pounces.
He fires a left to the body and a left hook to the head.
Huck drops his hands, and Glowacki shoots a slashing right. Huck slumps into the corner. Glowacki hammers away with three heavy lefts, the last one to the side of the neck, and pounds Huck through the ropes.
The final flurry was so vicious that referee David Fields had to hold up Huck until the ring doctor could get through the ropes.
“When things like that happen it shows you how amazing the sport is. The amount of determination sometimes, digging down a little deeper–I thought Glowacki was willing to dig down a little more than Huck was in the end,” TV analyst Paulie Malignaggi said.
In a year with several other brawls all deserving of the title–such as Leo Santa Cruz vs Abner Mares, Andrzej Fonfara vs Nathan Cleverly, Edwin Rodriguez vs Michael Seals–it's the dramatic slugfest between two Europeans that earns the PremierBoxingChampions.com editors' pick as Fight of the Year.