By Jake Donovan

Less than 36 hours after Anselmo Moreno returned to the ring with a dominant performance, the long-reigning titlist was served an emphatic reminder that the title of world’s best bantamweight is still very much up for grabs.

Shinsuke Yamanaka made the fourth defense of his version of the bantamweight crown, knocking out Jose Nieves in one round Monday evening in Tokyo, Japan.

A straight left hand was enough to put the visiting Puerto Rican challenger down and out, unofficially at 2:40 of round one.

Beginning with Koki Kameda's title defense win over John Mark Apolinario, all four major titles within the bantamweight division have been on the line within the span of the past 17 days.

The stretch has seen Tomoki Kameda - Koki's younger brother - put his family in the record books after lifting a belt from Paulus Ambunda earlier this month. With Moreno reminding the world of his capabilities in Saturday's ring return, the onus was on Yamanaka to prove why he deserves to sit on top of the mountain.

Less than three minutes later, it was mission accomplished in Tokyo. The defense was by far the easiest of Yamanaka's stay at champ, a run approaching two years. Nieves touched ground in Japan early last week, brimming with confidence and convinced that he had something that none of the other challengers boasted in their own shots at the defending champ.

Whatever he believes it to be, it wasn't punch resistance. It didn't take long for Yamanaka to make his presence felt, nor to remind the challenger that he had any intention of going away quietly. Nieves never even had the chance to land anything significant in his first shot at a major title.

Yamanaka went on the offense early, and remained in control for the duration of the brief encounter. Nieves just seemed to linger around until the incoming proved to be too much.

That moment came in the form of a perfectly timed straight left hand from Yamanaka towards the close of round one. The shot was enough to put Nieves down for the bout's lone official knockdown and also enough to signal an end to the main event.

Yamanaka advances to 19-0-1 (14KO) with the win, picking up his third straight knockout in the process. Dating back to his Nov. '11 vacant-title winning effort over Christian Esquivil, Yamanaka has scored a knockout in all but one of his title fights to date. The lone bout to go the distance was his first title defense, a unanimous decision win over former two-division champ Vic Darchinyan last April.

Nieves heads back to Puerto Rico with his first loss in more than three years as his record falls to 22-3-3 (11KO). All three defeats have come against unbeaten fighters, previously coming up short against Chris Avalos and Victor Fonseca. The loss ends a five-fight win streak, all of which appeared on Telemundo.

With three of the four bantamweight titlists now fighting out of Japan, it would be thought that unification would be the next logical step for Yamanaka. However, the Japanese southpaw stands a better chance of landing a title fight with Moreno. Yamanaka fights on Nihon TV, which aired Monday's twinbill, while the Kameda family plies its trade on TBS Japan.

A showdown with Moreno is highly unlikely until someone can put up the type of cash to convince either side to travel halfway around the world to face the other. Until such a fight happens, they will both have to continue to impress in their own separate ways and let the rest of the boxing world debate as to who is better.

Moreno attempted to do just that in Saturday's wide points win over William Urina. The feat was impressive. So, too, was Yamanaka's quick hit over Nieves - or at least a reminder of why he remains in the discussion.

In the opening bout of the telecast, World flyweight king Akira Yaegashi made the first defense of his crown with a unanimous decision over Mexico's Oscar Blanquet. The full fight report can be found

HERE

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Also on the show, former two-division champ Hozumi Hasegawa (33-4, 15KO) made quick work of Genaro Campargo, scoring two knockdowns en route to a 1st round knockout. With Yamanaka's bout ended 11 rounds earlier than was allotted in the broadcast, Hasegawa's feat snuck onto the airwaves via tape delay.

Jake Donovan is the Managing Editor of Boxingscene.com, as well as the Records Keeper for the Transnational Boxing Ratings Board and a member of Boxing Writers Association of America. Twitter: @JakeNDaBox