This time around, Julio Cesar Martinez made the stoppage ending stick.

A relentless pace set by Mexico's Martinez proved too much for Nicaragua's Cristofer Rosales en route to a 9th round stoppage in their vacant flyweight title fight Friday evening at Talking Stick Resort Arena in Phoenix, Arizona. 

There weren't any knockdowns in the fight, but an accumulation of punishment forced the stoppage at 1:19 of round nine.

Martinez forced a frenetic pace early in the fight, with Rosales willing to trade despite his preference to box. Winging shots by Martinez frustrated the former titlist, who fought behind the tight guard as he sought to throw and land straight down the middle.

The strategy paid off in round two, Martinez once again took the fight straight to Rosales, who buckled the knees of the compact Mexican slugger after scoring three flush right hands. Martinez was able to ride out the sequence, but had to contend with a cut over his right eye following an unintentional clash of heads. Rosales looked to capitalize on the sequence, but was clipped with an uppercut towards rounds end.

Action slowed ever so slightly in round three, deservedly so as both were high octane through the first six minutes. Martinez continued with his looping shots, while Rosales worked behind a range-finding jab in his best effort to put his 2 1/2" height advantage to good use.

Martinez continued to contend with a cut over his eye, but returned the favor legally in round four. Rosales was caught pulling back, his nose bloodied from a right hand by Martinez towards the end of the frame. Martinez took the attack downstairs in round five, while Rosales attempted to develop his left hook. 

Both boxers had success with left hooks to the body in round six, though Martinez getting the better of the exchanges. Rosales' stellar ability to absorb was put to the test late in the frame, when Martinez connected with a sequence of left hooks and uppercuts, ending the round with a left hook and right hand.

Momentum spilled over into round seven in a big way for Martinez, who was relentless in his attack. Rosales spent much of the frame on the defensive, taking a tremendous amount of punishment in the frame and drawing the concern of referee Raul Caiz Jr.

Rosales outworked Martinez in round eight, but only served as false hope. Martinez went straight to work in round nine, driving Rosales to the ropes and letting his hands go. A right hand and left hook left Rosales defenseless, forcing the third man to step in and intervene.

Martinez leaves the ring with the flyweight belt he thought he claimed four months ago, only for his 3rd round knockout of Charlie Edwards to get overturned when replays showed that Martinez struck the defending titlist while on a knee. An immediate rematch was ordered, only for Edwards—who won the strap following an upset win of Rosales last December—to give up the title and move up in weight.

It worked out for Martinez, who improves to 15-1 (12KOs). He adds to the incredible year enjoyed by trainer Eddy Reynoso, the leading candidate for Trainer of the Year thanks to his preceding work with Saul 'Canelo' Alvarez and Ryan Garcia. Friday's performance delivers the cornerman the new flyweight titlist, with Martinez proving a handful for anyone in and around the weight.

Rosales suffers his second loss in his last three starts in falling to 29-5 (20KOs).

The bout streamed live on DAZN in supporting capacity to the super middleweight debut of Daniel Jacobs (35-3, 29KOs) versus a considerably heavier Julio Cesar Chavez Jr. (51-3-1, 33KOs) in a battle of former middleweight titlists.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @Jake Donovan