Chavez raised his record to 108-5-2 and 87 knockouts in beating the over-matched Robinson, a former contender in the super light-weight division. The scores on the three judge's cards were 100-88, 99-89 and 99-89.
Chavez hurt his right hand in the ninth round while landing a hard punch to Robinson's head. Afterwards, he gave Robinson credit.
"He was a lot tougher than they told me he was going to be," Chavez said. "He was a tough fighter."
Robinson had been only 3-7-2 in his last 12 fights.