It looked as though Hamer would be posing some serious questions to the unbeated record of Ruiz, although once the Top Rank star raised his game in the third session, the American decided that was enough.
Ruiz pushes his record to 21-0 and moves a step closer to a world title fight, possibly in the next eighteen months, and goes into the mix with the likes of Bryant Jennings and Tyson Fury on the fringes of the top level.
Earlier, Felix Verdejo continued his impressive rise with a shutout victory over a game Duanaaymukdahan Petchsamuthr, pounding the Thai fighter at will en route to a 60-53 win on all cards.
Petchsamuthr was deducted a point in the match-up for low blows, but in the end it was academic as skilful Puerto Rican Verdejo improved his record to 9-0 (six stoppages) with a dominant perfomance.
Also on the bill, Chinese superstar Zou Shiming made similar work of previously unbeaten Juan Tozcano as the 32 year-old amateur standout improved to 3-0 to the delight of the home crowd.
Shiming dished out some heavy punishment to the Mexican, but just didn’t have the power to get him out of there and had to settle for a 60-54 points win on all three judges scorecards.
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