Clarke is impressed by Saints' summer market work.
"Southampton come here having invested heavily over the summer," the Scot told the WBA website. "They've boosted their squad after a brilliant first season back up.
"They were comfortable in the league from January onwards last year. It's going to be a tough test for us.
"I think you saw today that we look in good shape.
"We're looking forward to a good game."
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