By Luis E. Pabón

Konstantin Ponomarev remained unbeaten with a 10-round unanimous decision over veteran Cosme Rivera in their welterweight bout Saturday evening at Celebrity Theater in Phoenix, Arizona.

Scores were 98-92 and 100-90 (twice) in favor of Ponomarev, in a bout that failed to live up to the energy of an entertaining undercard.

The show was originally scheduled to be headlined by heavyweight Andy Ruiz, who was forced to withdraw due to personal reasons. That left Ponomarev and Rivera to carry the load as the marquee attraction.

From an action standpoint, they failed miserably. A competitive undercard revved up the packed house, only for the night to come to a screeching halt as the main event dragged over 10 long rounds devoid of drama.

Ponomarev improves to 25-0 (12KOs) with the win; Rivera, a former title challenger much earlier in his career, falls to 37-19-3 (25KOs).

In the televised co-feature, Victor Castro enjoyed his first win - and fight - since late last year, scoring a third round knockout over Mexico's Pablo Becerra (7-6, 6KOs).

The bout began sloppy, with both fighters wild with their punches. Castro seemed to struggle to find his rhythm, perhaps the effects of ring rust after nearly a year of inactivity.

The local hero connected with a home run shot just before the bell to end round three, a right hand putting Becerra on the canvas.

Confusion followed, as the ringside inspector came racing into the ring to tend to a fallen Becerra, despite the fight not yet officially stopped by the referee, who at that point was given no choice but to call it.

The official time was 2:59 of round three.

Castro improves to 12-0 (6KOs). The 22-year old is trained by former World 122 lb. champ Israel Vazquez, who served double duty on the show as he always works as a color commentator for UniMas, which aired both bouts.

NON-TV UNDERCARD

Edgar Brito beat the fight out of Luis Montano in forcing a 4th round stoppage. Brito (3-0-1, 2KOs) boxed in the opening two rounds before exploding for the bout's lone knockdown in round three. Montano (2-1, 1KO) bravely beat the count but was battered in round four until the referee had no choice but to intervene.

Local light heavyweight prospect Trevor McCumby thrilled the hometown crowd with a 1st round knockout of Martin Verdin. A fusillade of punches pumped up the packed house and put down Verdin (20-19-2, 11KOs) for the bout's lone official knockdown. The visiting journeyman beat the count, but was pummeled by a hailstorm of punches from the 21-year old McCumby (17-0, 13KOs) before forcing the stoppage in round one.

Egidijus Kavaliauskas picked up his 7th straight knockout after stopping Eduardo Flores (19-15-3, 14KOs) in the opening round of their welterweight bout. Three knockdowns forced the stoppage in favor of Kavaliauskas (8-0, 7KOs) who represented Lithuania in the 2008 and 2012 Olympic Games.

With his 2012 Olympic teammate Vasyl Lomachenko watching in support at ringside, Oleksander Gvozdyk rose to the occasion, scoring a 5th round knockout of Lamont Williams (5-6-1, 2KOs).

Gvozdyk (3-0, 2KOs) scored a flash knockdown in round two before closing the show for real in round five. A right hand put Williams down and out, splattered under the bottom rope as he was counted out.

Kavaliauskas and Gvozdyk are both managed by Egis Klimas and trained by Robert Garcia.

Francisco de Vaca was given a stiff challenge from Victor Serrano (4-7, 1KO), even if the official scorecards didn't indicate as such. The unbeaten super bantamweight from Phoenix scored a six-round decision, with scores of 60-54 across the board missing the point in terms of what took place in the ring. The 19-year old de Vaca is trained by Roberto Alcazar, the former trainer of Hall of Fame boxer-turned-promoter Oscar de la Hoya.

Shane Mosley Jr. was forced to go the distance for the first time in his young career, and also dealt his first defeat as a result. Marchristopher Adkins scored an upset four-round split decision over the second generation boxer in their middleweight bout. Scores were 39-37 for Mosley Jr. (2-1, 2KOs) and 39-37 (2x) in favor of Adkins (3-1, 1KO). Mosley Jr. was escorted into the ring by his famous fighting father, former three-division world champion 'Sugar' Shane Mosley Sr., though was on his own once the bell rang and failed to impress the judges.

Daniel Velez Garcia (1-1, 0KOs) waited ten months for his second pro fight, but well worth it as he picked up his first career win with a 4-round decision over debuting Samuel Garcia (0-1). Scores were 40-36 across the board in the welterweight bout.

In the opening bout of the evening, Carlos Castro remained undefeated, scoring a 3rd round knockout of Jaime Gutierrez. The matchup of super bantamweights was fought at a brisk pace, with Gutierrez (4-9, 0KOs) coming to win. Castro (6-0, 3KOs) eventually seized control before forcing the stoppage when Gutierrez suffered an injury and could not continue. All six of Castro's pro fights have been at Celebrity Theater, though his last ring appearance coming exactly 52 weeks ago.

Luis E. Pabon is a freelance writer and a currently in his junior year at Arizona State University. He is NOT the sketchy referee by the same name. Follow Luis on Twitter: @JuanLechePabon.