Two first half goals were enough from the South-London club to overcome their promotion rivals as they leapfrogged Saints to go third in the table.
It was a first half dominated by the visitors as they took their well-deserved lead on the twenty-minute mark.
The pressure had been building from the first minute for the Eagles as they should have taken the lead after a quarter of an hour when Blanchard blasted the ball over the bar from ten yards out.
Just five minutes later, Palace capitalised on their dominance as a break down the left-hand side resulted in a well taken finish from Atkinson who drilled the ball low into the far-right corner past Rendell.
The lead was doubled just before the break as the league’s top goal scorer Elise Hughes tapped in from six yards out after following in a shot which cannoned off the post straight into the path of the clinical striker.
A lack of creativity for the south coast side continued into the second half as they struggled to find the final pass to unlock a strong Palace defence.
However, with fifteen minutes to go captain Lucia Kendall managed to poke home a fantastic inswinging free kick from the edge of the box to half the deficit for the home side.
Despite a late onslaught from the reds, they could not find an equaliser which would have been so crucial in their race for promotion.
Saints will be hoping to bounce back in two weeks time when they travel to the midlands to face another promotion rival Birmingham City.
An important win for Crystal Palace could see them carry this momentum into their next game against mid-table Blackburn Rovers.
