Kermit Cintrón (born October 22, 1979) is a Puerto Rican former professional boxer and online boxing writer.

While attending William Tennent High School in Warminster, Pennsylvania, he became an accomplished high-school wrestler on the same team as actor Mike Vogel.

Cintrón was featured on NBC on May 18, 2003, against Puerto Rican veteran Luis Rosario, and he won by knockout 59 seconds into round one.

[5] KO Magazine featured Cintrón in an article, which compared his punching power to that of Félix Trinidad and Thomas Hearns.

Still undefeated and now considered a rising star in the division, Cintrón was scheduled for his first world title bout against WBO welterweight champion Antonio Margarito on April 23, 2005, as part of the undercard of a Shane Mosley win by unanimous decision against the Guatemalan-American boxer David Estrada.

[6] In early 2006, Cintrón rebounded with a tenth-round technical knockout of Estrada,[7] thus reestablishing himself as a contender in the welterweight division.

Cintrón then won his first title belt in a match against Mark Suarez for the IBF crown that had been vacated on June 20, 2006 by Floyd Mayweather Jr.[8] On July 14, 2007, Cintrón was dominant in his first title defense, knocking down Argentine Walter Matthysse three times on his way to a knockout victory twenty-nine seconds into the second round.

[9] Prior to this match, Matthysse had never been knocked down by any opponent, although he had suffered a tenth-round technical knockout in May 2006 at the hands of Paul Williams.

[10] Cintrón lost his IBF title to Antonio Margarito by knockout on an April 12 broadcast of HBO's World Championship Boxing in a rematch from Atlantic City, NJ, on the undercard of Miguel Cotto vs. Alfonso Gómez.

In the sixth round, Cintrón fell to the canvas after receiving a one-two punch to the head and a body shot and did not get up before the referee concluded the protective count.

In the third round, Cintrón connected a solid punch, N'dou tried to counterattack and exchange but was ineffective, eventually returning to a strategy based on holds.

[13] However, after receiving a more lucrative offer, Cintrón decided to fight Sergio Martínez for the World Boxing Council's interim light middleweight championship.

The opening rounds held no meaningful action, with Cintrón holding an early edge due to his aggression and cleaner punching.

By the fourth round, Martínez started moving around with his hands down in an effort to draw Cintrón into a mistake, but to no avail, as there continued to be more clinching than punching.

Late in the seventh round, a left hand to the head hurt Cintrón, and after backing into the ropes, he went down to his knees before Martínez could attack.

One such exchange caused an entanglement between the fighters, sending Williams to the canvas and Cintrón through the ropes, where he landed on a media table abutting the exterior of the ring.

In April 2007, Floyd Mayweather Jr. publicly claimed that any boxer could make the transition into mixed martial arts and win.

"[16] Sloan argued that his wrestling background and "ferocious banging style" represented "a dynamic combination that would have given MMA contenders all sorts of trouble" had he completed the transition in his prime.

[17] Later that year, Cintrón expressed interest in accepting Conor McGregor's challenge for boxers to "come into his world" and step into the UFC octagon.

[18][19] In November 2019, Cintrón announced that upon retiring from boxing, he would try his hand at MMA, still feeling confident that his background in amateur wrestling would facilitate the transition.