The Villa's leading goalscorer will be missing from the side to face the Trotters for a place in the final after picking up a leg injury during the 1st leg at The Reebok last week.
“Angel will be out. I don’t know how long he’ll be out for," manager David O'Leary told the clubs official website.
“He picked-up an injury at Bolton and he won’t play. Well looking at it now, he won’t play unless there’s a miracle.
“He’s got a kick on his leg that’s tracked all the way down his leg. It’s a complicated one, but he’s out.”