Southampton have struggled recently, losing to Burnley 1-2 in the last time.
However, the AH line is still in favor of Southampton.
On the other hand, Aston Villa lost to Tottenham in the last time, which is a blow to their morale. So Aston Villa should not be overestimated in this game.
Besides, Aston Villa are superior in overall quality.
Thus, the hosts are expected to win.