MANILA, Philippines — Former two-division world champion and two-time Olympic gold medalist Guillermo Rigondeaux conceded defeat to heavy underdog Vincent Astrolabio whom the Cuban complimented for his speed, power and smarts in capturing the vacant WBC International bantamweight crown via a unanimous 10-round decision in Dubai last weekend. Astrolabio, 24, was a +600 bet, meaning a wager of $100 would earn $600 with his win, while Rigondeaux, 41, was a -1,000 favorite so that a $1,000 stake would only bring in $100. But the Filipino defied the odds to upset Rigondeaux who was decked by a left…