Two goals early in the second half from Dani Osvaldo and Rickie Lambert secured the three points for Saints, who moved in to the top four of the Barclays Premier League with the win.
After a first half of very few opportunities it was Osvaldo who grabbed his first goal for the club moments after the restart with a Lambert free-kick two minutes later proving enough to kill off Palace.
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Some sunny spells to start but turning cloudier through the day and staying breezy.
Dry but breezy tonight, cloud and some bright spells on Sunday.
Dry but breezy this evening and overnight with cloud and sunny spells tomorrow.