Almost three years after his wife filed for divorce, rock guitarist Carlos Santana is marching to a new beat with his drummer. The Grammy-winning virtuoso behind ‘70s hits such as “Black Magic Woman” and “Oye Como Va” proposed to Cindy Blackman onstage during his concert last Friday in suburban Chicago, his label said on Monday. There was no word on when the couple planned to marry. Santana, who turns 63 next week, was previously married for more than 30 years to Deborah Santana, the mother of his three children. She cited irreconcilable differences in her October 2007 divorce filing. In her 2005 memoir, “Space Between the Stars,” she revealed that her husband had been unfaithful. After its publication, Carlos Santana said he had apologized and tried to be a better man.