When Aston Villa last lost five matches in a row, Dean Smith paid with his job. The situation was not as severe for Unai Emery but he needed to end a dismal run of four defeats and was deeply frustrated that his side failed to turn domination into three points.

Ollie Watkins and Ross Barkley twice equalised for Aston Villa, who also had a Youri Tielemans penalty saved. They were twice hit on the break, resulting in Ismaïla Sarr and Justin Devenny giving Palace the lead. Villa were dominant from the start but lacked the cutting edge expected of a Champions League side.

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“We are making mistakes and teams are scoring so we are not getting the points we deserve,” Emery said. “There is still work to do. We are really convinced this is the way to play but we are not getting three points – we deserve, more or less, to win each match at home.”

Oliver Glasner set up his side to play on the break and it was highly effective. Jean-Philippe Mateta often looked like a man playing against boys with his strength, speed and ability to hold on to the ball as claret and blue shirts bounced off him. He created the first goal within four minutes, slicing open Villa with a pass for the lightning quick Sarr to chase, while holding off Ian Maatsen, before calmly slotting beyond Emiliano Martínez to silence all but a corner of Villa Park.

The pattern of the game was already set as Villa lacked the speed of thought and confidence that helped them qualify for the Champions League last season. It was a real moment of quality, though, that brought them back into the match. John McGinn spotted a trademark Watkins run, weighting the pass perfectly to tease Dean Henderson out of his goal, thinking he could get there first only to be beaten to it by the striker, who rounded the goalkeeper to score his first in six matches for Villa.

The equaliser energised Villa and Leon Bailey soon rattled the crossbar as they looked to complete the turnaround. Bailey was the protagonist for the penalty as Will Hughes stepped on his ankle inside the box.

The referee Tim Robinson gave nothing but was sent over to the screen by his colleagues. It seemed harsh to overturn the original decision and Hughes looked at the replay on the big screen with a confused smile. There was a wider grin when Henderson dived superbly to his left to palm away Tielemans’ spot-kick.

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Henderson was celebrating in front of the away end almost immediately when Palace broke from the resulting corner and the 21-year-old Devenny swept home his first goal for the club on his second appearance after a flowing move from back to front.

Villa had 70% of possession but managed to get only five of their 17 shots on target against a battling Palace. The hosts were often quite ponderous, struggling to find the right pass to open up a disciplined Eagles defence and needed a set piece to secure a draw.

The visitors had their backs against the wall through the second half with 11 men consistently behind the ball as they aimed to hold on for victory. It seemed inevitable Palace would fail to leave with the points and it was Barkley who made the most of being unmarked to flick in from a Tielemans corner. The midfielder was given too much space, after a rare lapse in concentration from Palace, at the near post before running away sucking his thumb in celebration.

“There are two emotions that I have,” Crystal Palace head coach Glasner said. “First of all the biggest one is being proud of the team, the performance and style in the circumstances in missing attacking players but still scoring two fantastic goals. I am really proud of how we defended together and scored the goals. The other emotion is one of disappointment because we led twice and conceding the second from a set play is not so good.”

Jeffrey Schlupp almost provided a surprise winner for Palace when he hit the post with 10 minutes to play but the points were shared. Villa have stopped the rot but with Juventus in town on Wednesday, they know improvement is required.