DJ Campbell has urged Birmingham to bounce back quickly following successive defeats over Easter.
Blues lost 1-0 against Burnley on Saturday, before falling to the same score line at Barnsley on Easter Monday.
Steve Bruce's side are now third in the Championship as they chase a return to the top flight at the first attempt.
And Campbell wants to see an improvement when George Burley's Southampton visit St Andrews at the weekend.
"It's hard to explain Burnley and Barnsley, I was left gob smacked," he told the Birmingham Mail.
"We can definitely still go up but we need to change things around straight away.
"Losing to Burnley and Barnsley was not good enough. We should have been winning those games.
"It hasn't gone our way and it's just at the wrong time.
"It's the business end of the season, now is when it matters. So we know we've got to put it right."