The first HBO boxing card of 2012 is officially upon us as all participants made weight Friday afternoon for Saturday’s televised doubleheader live from the Alamodome in San Antonio.

In the main event, Julio Cesar Chavez Jr makes the second defense of his alphabet middleweight title as he faces countryman and former title challenger Marco Antonio Rubio.

Chavez Jr (44-0-1, 31KO) weighed just below the middleweight limit at 159.5 lb, though stripping down to his birthday suit with blanket in front of him, lending to week long rumors of his struggling to make weight or half-assing it during training camp. The always professional Rubio came in at 159 lb.

The bout marks Chavez Jr’s third straight HBO Boxing After Dark appearance, which has covered his entire middleweight title run. The second-generation titlist won the belt in taking a narrow decision over Sebastian Zbik last June in his HBO debut, then defended five months later with a 6th round stoppage of Peter Manfredo Jr.

Rubio (53-5-1, 46KO) makes his network debut, having previously appeared on HBO PPV undercards. The bout marks his second crack at the middleweight title, falling short to then-lineal champ Kelly Pavlik nearly three years ago. He has since won ten straight, including his last six by knockout.

In the televised co-feature, pound-for-pound entrant Nonito Donaire rises in weight as he takes on former 122 lb. titlist Wilfredo Vazquez Jr. The bout will be for a vacant belt, but has also developed into a grudge match between the two camps over the course of fight week.

Donaire (27-1, 18KO) clocked in at 121.6 lb., the heaviest of a career that has now spanned four weight classes. The Fil-Am boxing star has won major titles at flyweight and bantamweight, including a title-winning 2nd round knockout of Fernando Montiel a year ago in a performance hailed by many as the Knockout of the Year.

Vazquez (21-1-1, 18KO) hit the scales at the divisional limit of 122 lb. The son of former three-division world champion Wilfredi Vazquez Sr, the diminutive Boricua is nine months removed from a 122 lb. title stint, having lost his crown to Jorge Arce in a heartbreaking 12th round stoppage defeat, the first of his young career.

The HBO Boxing After Dark broadcast begins at 10:00 PM ET (tape-delayed on the West Coast). Doors open at 5:30PM local (Central) time, with the non-televised undercard set to begin soon thereafter.

Other weights:
Vanes Martirosyan, 153.5 lb vs. Troy Lowry, 153.75 lb. - 10 rds, super welterweight
Wale Omotoso, 147.25 lb. vs. Nestor Rosas, 146.5 lb. - 8 rds, welterweight
Raul Hirales, 122.5 lb. vs. Shawn Nichol, 122.5 lb. – 8 rds, super bantamweight
Ivan Najera, 136.5 lb. vs. David Castillo, 136.5 lb. – 4 rds, lightweight
Alex Saucedo, 146.75 lb. vs. Jean Colon, 143.5 lb. – 4 rds, welterweight
Adam Lopez, 115.75 lb. vs. Richard Hernandez, 114.5 lb. – 4 rds, bantamweight
Jeremy Longoria, 126 lb. vs. Ricardo Valencia, 125 lb. - 4 rds, featherweight

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