Benitez saw his side slip nine points behind leaders Chelsea following theirdisheartening 3-1 defeat at Fulham on Saturday, when they also had defendersPhilipp Degen and Jamie Carragher sent off.
Ful of it: Bobby Zamora scores the first goal on what was an afternoon to forget at Craven Cottage for Liverpool
Whelan believes the loss was preventable, however, highlighting Benitez's decision to substitute star striker Fernando Torres after an hour when the scores were locked at 1-1.
Euro fool: Anfield hero Whelan has slammed Benitez for prioritising the Champions League
Torres has been struggling with injury in recent weeks, but regardless Whelan - who won six league title during his career at Anfield - believes the decision to withdraw him was reflective of Benitez's priorities ahead of the Reds' Champions League trip to Lyon on Wednesday.
'It's all gone wrong with the manager and he's shown exactly where his priorities lie,' said Whelan.
'He wants to win the European Cup so he can get a job in Europe. For me, his days have got to be numbered at Liverpool.
'He's taken players off who are the only players who are going to give you a chance of winning the game.
'And he drags them all off because he's got a game on Wednesday.
'When I saw the team I thought he's not bothered about this game.
'He's putting all his eggs in one basket and I can't see why he's done it.'
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