MASHANTUCKET, CONN. – Rapper/promoter Curtis “50 Cent” Jackson’s impact on the sport of boxing has already been significant. His presence alongside the boxers he now promotes automatically raises their profile and exposes them to a higher level of scrutiny than they had ever been under before.

Jackson, whose upstart SMS Promotions outfit co-promoted this week’s ESPN2 Friday Night Fights with DiBella Entertainment, accompanied IBF featherweight titleholder Billy Dib, his only fully recognized world champion under contract, performing his single “New Day” en route to the ring for Dib’s title defense against Evgeny Gradovich at Foxwoods Resort.

But at the end of the day, you still have to fight. After a grueling twelve rounds, late-replacement Gradovich was hoisted above his handlers’ shoulders as the new titleholder as a bloodied Dib remained in the ring despondent. The scores were 114-112 on two cards for the late-replacement Gradovich of Igrim, Russia, while the third had it 114-112 for Dib of Sydney, Australia. Jackson left the ring before the scores were announced.

Gradovich (16-0, 8 knockouts) took the fight on a month’s notice after Cuban Luis Franco unexpectedly withdrew from the fight and announced his retirement. The 26-year-old known as “The Russian Mexican” joins the ranks of Nonito Donaire Jr., and Brandon Rios as champions trained by Robert Garcia in Oxnard, Calif.

Ironically, it was another Garcia-trained boxer Steven Luevano who handed Dib his only prior career defeat in 2008.

The heavily-favored Dib (35-2, 21 KOs) won the first two rounds easily, utilizing his superior speed and skills to outhustle the slow-starting Gradovich, digging to his midsection. Around the third, Gradovich began to impose his will on Dib, who was making his third defense of the title he won with a decision victory over Jorge Lacierva in 2011. Gradovich made his first big statement of the fight in round five, stunning Dib with a left hook that pushed him back. An elbow later in that exchange produced a cut on Dib’s scalp.

By round seven, Dib began to back up and look for counterpunch opportunities, resigning that he couldn’t content with Gradovich’s superior power and strength. Dib showed a tremendous amount of heart in surviving the hard, clean power shots that Gradovich began to land more frequently.

By round 11, Dib had another cut on his right eye and one on his forehead to contend with. Heading into the final stanza, Dib dug deep looking for a dramatic knockout but Gradovich stunned him once more with a left hook with a minute left. The crowd booed the split decision announcement but cheered the official verdict.

Meanwhile, in the co-featured bout, junior middleweight Willie Nelson (20-1-1, 12 KOs) made about as big a statement as he could’ve on the stage given him as he knocked out Michael Medina (26-4-2, 19 KOs) at 2:00 of round one. The lanky Nelson, 25, of Cleveland, Ohio took advantage of Medina’s reckless rush, catching Medina with a right hand off the ropes as Medina threw a right of his own. Medina rose up but was dropped hard with another right, prompting the referee to end the fight.

With “KO KING” emblazoned on the back of his trunks, Luis Rosa, Jr. worked his hardest to live up to the moniker. Rosa, 21, from New Haven, Conn. loaded up on each punch he tossed at Jhovany Collado from Queens, N.Y., and looked to be going home early when a left hook dropped Collado late in round one. Yet despite being stunned often by the heavier-handed Rosa, Collado fought bravely and survived to hear the wide decision in favor of Rosa.

Rosa (13-0, 6 KOs) won every round on the judges’ scorecards, finishing with a tally of 80-71 on all three cards.

In the show’s opener, featherweight Ryan “The Polish Prince” Kielczweski (16-0, 3KOs) won a unanimous decision over Gil Garcia (5-4-1, 1 KOs) of Houston, Tex. by the scores of 80-72 on two cards and 79-73 on the third. Kielczewski, 23, of Quincy, Mass. used his superior height and reach to keep the aggressive but crude Garcia on the outside when he wanted to, and outgunning him with superior power when he wanted to. Despite the relatively easy victory, Kielczewski is still a work in progress.