Harvey Elliott ended Villa's goal drought but it was not enough to prevent them from being knocked out 4-2 on penalties after a 1-1 draw.

Elliott, signed on deadline day on loan from Liverpool to pep up Villa's misfiring attack, scored their first goal of the season on his full debut thanks to an error from Bees goalkeeper Hakon Valdimarsson.

But after Aaron Hickey scored a spectacular volley to equalise for Brentford, Valdimarsson made amends by saving from John McGinn and Matty Cash in the shoot-out.

Mikkel Damsgaard then rolled in the winning penalty as Brentford celebrated a place in the fourth round.

Emery, whose side drew two and lost two of their first four Premier League matches, said: "We improved things. We played 90 minutes with good balance to dominate and creating chances.

"We scored one goal, positive. We drew. And the penalty shoot-out we lost so we are disappointed.

"We have to get strong defensively and offensively and get in combination good performances. Today is one part of the way. Not with the result we wanted but we have to accept it.

"There is still a lot of work to do, a lot of practice and matches. I think we are watching some improvement. Not enough but a lot of things will be positive."

Icelander Valdimarsson's performance in the shoot-out was all the more remarkable after he needed treatment on a cut above his eye.

He was then badly at fault for Villa's goal when he let Elliott's weak shot roll through his legs.

The 23-year-old stand-in keeper told Sky Sports: "I was pretty scared that my contact lenses had come out - but the eye is good.

"A great win. I'm so happy. I maybe should have saved their goal. But very happy with the performance.

"When I saved the first penalty, I knew we were going to win it."

Bees boss Keith Andrews said: "Goalkeepers are always involved in the moments aren't they?

"I said at half-time mistakes will happen. I'm OK with that. The reaction I'm really happy with, two great saves in the shoot-out."

It was a special moment for Scotland full-back Hickey, scoring his first goal for the club after missing most of the last two seasons through injury.

"He's a talented player and to score a goal of that quality was special for him," added Andrews.

Aston Villa boss Unai Emery takes positives despite shoot-out loss at Brentford