By Miguel Rivera

Two-time Olympic gold medal winner Guillermo Rigondeaux believes countryman, unbeaten heavyweight contender Sullivan Barrera (17-0, 12 KOs), will have a very tough task later tonight when he faces former super middleweight king Andre Ward (28-0, 15 KOs).

They are set to collide at the Oracle Arena in Oakland. The bout will be televised live on HBO World Championship Boxing® beginning at 9:45 p.m. ET/PT.

NABF featherweight champion Joseph "Jojo" Diaz Jr. (19-0, 11 KOs) and top-rated featherweight contender Jayson "Star" Velez (23-1-1, 16 KOs) will clash in 10-round fight which will open up the HBO telecast.

This is Ward's first bout at the light heavyweight limit. The winner will be guaranteed a fall shot at IBF/WBA/WBO world champion Sergey Kovalev, who plans to make another defense in June.

Like Rigondeaux, Ward is an Olympic gold medal winner. Rigondeaux is caught in the middle with this matchup. He wants to support his countryman, but he wants to cheer on his stablemate as well. Rigondeaux and Ward share the same promoter in Roc Nation Sports.

He say Barrera must not waste his punches and make every shot count when facing a boxer like Ward.

"Ward comes from the Olympic school of boxing and he knows how to move well to avoid punches, '' Rigondeaux said to George Ebro. "If Sullivan comes right at him like a bull, Ward is going to punish him. Sullivan must press and apply good pressure, but he must also look for the right openings, think before he does things, and look to do damage instead of throwing punches just to throw them."