The visitors have had the better chances but faded away as the first 45 minutes wore on.
Southampton started very quickly and created several good chances in the opening 10 minutes.
First, Luke Shaw burst down the left and crossed for Rickie Lambert to head straight at the goalkeeper, before Lambert was again found in the box. This time though, he saw his shot blocked by Ron Vlaar.
Villa steadied their ship but Southampton continued to threaten thanks to late runs from Adam Lallana and James Ward-Prowse, before Steven Davis forced an excellent save from Brad Guzan after the American goalkeeper had failed to deal with a cross.
The Saints continued to dominate possession but threatened less and less as the half drew to a close.