Austin was acquired from Queen's Park Rangers in the morning, then watched from the stands as James Ward-Prowse scored twice and Dusan Tadic finished off a victory which separated them from West Brom in the middle of the table.Prowse, an England Under-21 midfielder, was an unlikely star as he had scored in the league only once before. But he scored within five minutes from a free kick, bending it over the wall.
"The free kicks are one of his qualities," Southampton manager Ronald Koeman said.
"It's important for the boy, it will lift his confidence. And that free kick was so important to break open the game. Then, when you are 1-0 up, West Brom have to do more and do things differently."
Prowse became the first Southampton player to score directly from a free kick since February 2014.
He doubled his tally from the penalty spot before halftime.
Tadic was the regular penalty taker, but he was on the bench until just after an hour had passed. Tadic scored only eight minutes later, firing on the angle after being played into the area by Steven Davis.
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