PA's best run for a number of years is at an end after they went down 2-1 to the Brakes in the Vanarama National League North. Watch Match Highlights Here.
Bower doesn't want the defeat to be the start of a downward spiral for Avenue.
They will have to get their heads together quickly as they have the hardest possible draw in the FA Cup on Saturday - away to league leaders Harrogate Town.
The manager told his side that they couldn't take anything for granted against a Leamington side who were at the wrong end of the table but he said he warning was not heeded.
Bower told the Telegraph and Argus: “We just didn’t play well on Saturday - too many players were off the boil.
“I’m the first to praise the players when they do well, and they have been doing well, but we were below par.
"It was never going to be an easy game. Leamington are a strong side who are always tough to beat.
“What’s important now is how we come back from it because we have a very tough FA Cup tie at Harrogate Town next.”
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