Mayweather is maybe the most obvious one although some people think Castillo out pointed him in their first match. And Vitali was always up on points. What other boxers were always up on points during their entire career as pros in their wins and even when they lost?
In about his 55th fight, by split decision. It was the only decision he ever lost. If we look that deep we pretty much have to look at fighters that were never defeated or who had short careers.
Jemal Hinton- He went 98-14 as an amateur including a win over Kennedy McKinney in April of 1988 for the U.S. Title. In July of 1988 he lost to McKinney in the Olympic trials. McKinney would win a Gold medal and become a 2x SBW/JFW world title holder. As a pro he went 22-0 (17) overall and 5-0 (4) in WBC Americas SBW title fights.
Their film records aren't complete, but Tunney-Loughran must have been something along those lines. I strongly suspect Duran would offer up Ken Buchanan prior to Ken's comeback. He was saying on camera even while interviewed during a quicker win in the mid 1990's (maybe after Mike Culbert) that Buchanan was the best opponent of his career. He was in a relaxed mood at ringside for reviewing his career after and easy stoppage, and if it was indeed Culbert, this would have been after many thought he got the better of Camacho in their first bout, so he didn't have much more to experience in the way of opposition. Michael Spinks could provide an argument. So could Miguel Canto. One ATG who might not modestly allow the inclusion of his name on this list might be Willie Pep. He said stylists like New England rival titlist Sal Bartolo gave him a lot of trouble, and in fact he produced the signature knockout win in their rubber match by breaking Sal's jaw with a right in round 12 to unify all FW title claims. They had three bouts prior to Pep's plane crash, and while Willie dominated their middle bout, he seems to have been unusually aggressive with his underrated power in all three matches. Pep-Bartolo III was only Sal's second stoppage loss in 98 outings, and the only time he was counted out. We have footage of Willie blasting out McAllister in 1946 with a hook to the body to avenge a previous draw, and as Pep himself said, "I could hurt you!" Willie tended to spare his hands because he fought so much, but it was apparent to observers when he was atypically looking for a knockout. Reports do not suggest he played much chess with Bartolo, and he told a late friend of my father's who idolized him that he really overpowered and outgunned Sal rather than outbox him. Here, I'm not asserting any definitive answers or opinions, just ideas as starting points, and in Pep's case, an exception he indicated in his own career, depending on how literally we interpret NEVER outboxed. Locche racked up 117 decision wins, mostly in Argentina, under a scoring system which issues an automatic draw for a margin of less than three points by the judges.
Buchanan was miles behind Duran and had lost previously on decision. Superb boxer but a long way from the criteria. Very interesting footnote tho, as usual.
It was very early in Tommy's career, and I've never seen it, but my understanding is that Harold Weston, Jr. was competing closely with Hearns until a detached retina ended the match as well as Harold's career. No, he's not a candidate for this thread, but he could box on even terms with just about anybody. Drew with Mamby, Hegemon, Benitez, and UDed Andy Price. Only stoppage win of even the remotest note on his record was a TKO over Antuofermo (on cuts of course). Harold banked everything on winning the decision. Very smart early in retirement as well with uncanny accuracy at predicting major bout outcomes.
When was Marco Antonio Barrera ever outboxed? He was roughed up Junior Jones early on in his career, but he rehydrated to 139 pounds at superbantamweight. That fight shouldn't have been sanctioned. And then roughed up again by Pacquiao.
I do remember that struggle with Weston actually. The cagey veteran gave the green Tommy some trouble, absolutely.