Grealish set up Hourihane and won the spot-kick for Abraham to win it and Smith praised his skipper.
"Jack got on the ball - and that's what we want from him".
Taylor and Joe Aribo netted in the first half for the Addicks, only for Matty Blair to give Rovers hope.
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But Smith expects more from his side after they were forced to battle back from a goal down at Villa Park on Saturday. I expect a different game, that's for sure'. We can certainly perform a lot better. We created more opportunities but it took a really good shot from Hourihane to get us back into it.
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With Gayle missing, Shan will look to Jay Rodriguez to spearhead the frontline.
Villa won a penalty four minutes later when midfielder Jack Grealish was brought down by defender Kieran Gibbs and Abraham, on loan from Chelsea, held his nerve to slot the ball in for the victor.
Albion's woes were compounded with two minutes left when Gayle slid in to reach James Morrison's cross but clattered Steer and saw red.
Whelan told Football Insider why Hourihane should have started the first leg and deserves to come into the side for the second game at the Hawthorns. "To my mind, every time the ball went out he had an intent of walking towards to the ball", he said.