Southampton returned to the Premier League after a seven year absence when they beat Coventry City 4-0 on Saturday to clinch second place in the Championship (second division) and take the remaining automatic promotion spot.
West Ham United, who could have pipped Southampton if results had gone their way, finished third after beating Hull City 2-1 at Upton Park and will take part in the playoffs along with Birmingham City, Blackpool and Cardiff City.
Champions Reading, who clinched the title last week, lost 2-0 at Birmingham.
West Ham will now meet Cardiff in one semi-final playoff, while Blackpool will play Birmingham in the other. Those games are decided over two legs with the final at Wembley on May 19.
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