Brighton were twice denied an opener during a crazy spell in which they missed a penalty and had a goal disallowed after two VAR calls in two minutes.
Pascal Gross’ tame attempt from the spot was repelled by Palace goalkeeper Jack Butland after Joel Veltman was adjudged to have been fouled by Will Hughes at a corner following VAR intervention.
Palace’s travelling fans, who threw a flare onto the pitch before Gross’ kick, had barely finished celebrating the save when Neal Maupay put the ball into the net moments later.
Referee Robert Jones was once again called to the pitchside monitor and subsequently ruled Maupay had bundled the ball out of Butland’s hands.
Leo Trossard also missed a golden chance in the first half when his effort was well by Butland's legs.
Palace snatched the lead in the 69th minute through Conor Gallagher.
The on-loan Chelsea midfielder emphatically fired his seventh Premier League goal of the season into the right corner after Jeffrey Schlupp pulled the ball back.
Brighton levelled with three minutes remaining.
Maupay worked his way into the box past Joel Ward and his centre was inadvertently turned his own net by Palace defender Joachim Andersen.
Here's who shone and who struggled for Graham Potter's men at the Amex Stadium.
Rob Sanchez 7 No chance with the goal. Looked calm and composed. Commanded his box well in the early stages, and produced a fine save at the start of the second to keep out a block from Webster
Marc Cucurella 6 Decent display down the left flank. Always looking to move forward with purpose and rarely gives the ball away
Adam Webster 8 Very good performance from Webtser. Defender well and excellent distribution from the back. Very impressive.
Neal Maupay 7 Had a goal disallowed when he bundled the ball out of Butland's hands in the first half. Worked hard as always got his reward when his cut back was turned in by Joachim Andersen
Alexis Mac Allister 7 Enjoyed his performance. Clever on the ball and one pass to tee-up Moder just after the break was a delight.
Leo Trossard 6 Excellent early chances but denied by the legs of Jack Butland. Some nice touches but drifted in an out of the match
Pascal Gross 5 Terrible penalty in the first half overshadowed a solid display. Withdrawn on 72 minutes for Solly March.
Adam Lallana 6 Played a deeper role and did everything with skill and guile. A high level display and ensured Bissouma was not greatly missed. Hobbled off in the second half.
Jakub Moder 7 Always looking to run in behind. Intelligent movement and seems to get better with every appearance. Unlucky not to score after the break.
Dan Burn 7 Tried all he could to block Gallagher's effort from going in. Consistent performance from the defender.
Joel Veltman 7: Selected ahead of Lamptey and proved his worth. Excellent one-on-one defending and provided some good deliveries into the box. Replace don 70 minutes for Welbeck
Tariq Lamptey 6: Came on for Lallana and bombed up and down the right flank. Just couldn't make that telling impact
Solly March 6 Looked to find the gaps and teed up Welbeck for a late chance
Danny Welbeck 6 Some nice touches and headed a difficult chance just over in the dying moments
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