Zaha ended a lengthy goal drought just before half-time when he fired home after a sweeping Palace move, but a second half strike by James Ward-Prowse levelled things up.
The two goalscorers then got involved in some heated words in the dying stages which saw the Eagles attacker booked, and for his subsequent protestations he picked up a second yellow, leaving Roy Hodgson’s team to cling on to a point.
On a brisk night on the south coast, there was little to warm those in attendance during the first half but Palace looked the livelier in attack in the opening 20 minutes and Jordan Ayew was a whisker away from connecting with a diving header following a corner, and James McArthur scuffed a sight of goal well wide from the edge of the area.
It took the Saints until midway through the first half to force Vicente Guaita into a save when Danny Ings won possession from Mamadou Sakho on the touchline and weaved inside before finding Pierre-Emile Hojbjerg, but the captain’s low first-time effort was parried well by the Eagles custodian, and that looked to be as eventuful as the first period would get, but four minutes before the break that all changed as Palace finally got the goal their better positivity deserved.
Cheikhou Kouyaté turned away from Jannik Vestergaard just inside the box and fired a low centre towards Ayew who nudged it back to Andros Townsend. He managed to nick the ball into Zaha just before being taken out by a sliding Oriol Romeu, but a good advantage played by Andre Marriner allowed the Ivorian to get the ball under control and power it past Alex McCarthy at his near post to score his first goal since September.
The second half began with Ings shooting straight at Guaita from a tight angle, but after that scare on 52 minutes the Eagles could easily have found themselves 2-0 ahead when a dangerous Luka Milivojevic corner was swerved into a packed six-yard box and McCarthy, under pressure from a host of players, went down softly from minimal contact from James McArthur, which saw play halted just before Sakho drove the ball home from close range.
Once again the game fell into a lull which the visitors didn’t mind being in possession of the lead, but they continued to look the more threatening and Townsend whipped a shot over the top, and more poor defending from a corner allowed Sakho another opportunity to find the net but this time his shot was hooked off the line by Hojbjerg.
And that proved vital as with 13 minutes to go, the hosts pulled level with their best move of the match. A slick passing move involving Nathan Redmond, Stuart Armstrong and Matt Targett down the left allowed the full-back a chance to pick out a teammate inside the area, and he did just that to allow Ward-Prowse the chance to tuck into the bottom corner of Guaita’s net.
With parity restored, suddenly it was game on and both teams started pushing for the vital extra two points. Armstrong forced Guaita into a flying save when he attempted to find the far corner with a curler, but back came the Eagles and Milivojevic caused McCarthy some concerns with a long range strike that he scrambled clear.
However he was left in no-mans-land seconds later when he misread yet another corner which allowed Sakho the chance to regain the lead, but this time the Frenchman couldn’t hit the target and a huge chance went begging.
Then with three minutes to go Zaha saw his evening end on a sour note when he was shown his marching orders. Having been fouled by Ward-Prowse, he got in a confrontation with the England international and received a booking from Marriner, for which he sarcastically clapped the official, leading him to receive a swift second yellow and leave his team with 10 men.
Insult could have been added to injury soon after when Guaita misjudged a cross and allowed Armstrong a shot at goal, but the keeper recovered quickly and managed to snuff out the chance to ensure the points were shared.
Southampton: McCarthy, Bednarek, Stephens, Vestergaard (Elyounoussi 75), Valery (Armstrong 62), Ward-Prowse, Romeu, Hojbjerg (Slattery 84), Targett, Redmond, Ings. Subs not used: Gunn, Ramsey, Gallagher, Long.
Palace: Guaita, Wan-Bissaka, Tomkins (Dann 90), Sakho, Van Aanholt, Kouyaté (Schlupp 71), Milivojevic, McArthur, Townsend, Zaha, Ayew. Subs not used: Hennessey, Kelly, Meyer, Wickham, Benteke.