Roy Hodgson has got some help in his battle to keep up Palace - Christian Benteke is back scoring.
After 1106 minutes and 13 games - including that missed penalty against Bournemouth - Benteke headed one in.
Then the Big Man celebrated with a powerful run that left Leicester players in his slip stream to set-up man of the match Wilfried Zaha for Palace’s second.
Both goals came before half time and if the Palace fans in the King Power Stadium partied all through the break you could understand why.
These were the first goals Palace have scored away all season.
When Wilfred Ndidi dived to try and get a penalty in the 62nd minute and was sent off for a second yellow card the problems got even worse for Leicester and they couldn’t solve them.
Not the best way for Ndidi to celebrate is 21 birthday and not a great day for his team either.
They fell to their second defeat in Claude Puel’s ninth game as boss and their charge up the table halted.
Palace are now unbeaten in seven games and Hodgson’s team are looking well capable of getting out and staying out relegation trouble.
Ahead of the rest of today’s games, Palace are out of the bottom three by a point, shoving West Brom down there who don’t play until Sunday.
Benteke’s return to scoring form could be crucial. He headed in a six yarder from Andros Townsend’s excellent 19 minute cross , but Puel will be wondering why it wasn’t defended better.
Then, after almost giving Leicester an own goal equaliser with an intended headed clearance that was dangerously near the post, Benteke powered off on a 40 minute run that finished with Zaha beating Ben Chilwell and scoring a classy goal.
Riyad Mahrez brought a couple of saves out of keeper Julian Speroni, but Palace were well worth their first away win with sub Bakary Sako getting a third in added time.
Leicester: Schmeichel, Simpson, Morgan (c), Maguire, Chilwell, Iborra, Ndidi, Mahrez, Albrighton, Gray, Vardy.
Subs: Hamer, Fuchs, Dragović, King, Okazaki, Iheanacho, Ulloa
Crystal Palace: Speroni, Kelly, Dann, Tomkins, Schlupp, McArthur, Cabaye, Loftus-Cheek, Townsend, Zaha, Benteke
Subs: Hennessey, Van Aanholt, Souare, Lee, Sako, Wan-Bissaka, Riedewald.
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Palace go 2-0 up
Welcome
Leicester boss Claude Puel has offered no guarantees record signing Islam Slimani will stay with the Foxes.
The striker has played just 10 minutes since Puel was appointed manager in October.
He has failed to impress since a £30million move from Sporting Lisbon in August 2016, netting 12 times in 41 games.
Leicester spent £25million on Kelechi Iheanacho in the summer while Leonardo Ulloa, Shinji Okazaki and Ahmed Musa are also options to support Jamie Vardy, and Puel remained coy on Slimani’s future.
“Time will tell to speak about the January transfer window but he is in the squad,” Puel told a press conference ahead of Saturday’s visit of Crystal Palace.
“He was on the bench for the first game. He provides the same option as Ulloa because Ulloa works very well in the training session, harder.
“I think now Slimani is working very well also. It is always difficult for me to make assurances with competition between the players.
“It is difficult for me to say what will happen in the transfer window but it is difficult for me and the staff to manage all these players for the same position.
“But they all work like Slimani, Ulloa, Iheanacho and Musa, different players they work very well.
“It is very difficult for me to leave some players off the bench.”