The former Wales coach frequently hits out at leading Premier League managers over how they handle their players, in particular Arsenal boss Arsene Wenger.
And after Liverpool crashed out of the EFL Cup to Southampton last night, Verheijen took a swipe at Klopp.
Twitter reacts as Liverpool are knocked out of EFL Cup by Southampton
Wed, January 25, 2017
Express Sport brings you all the best tweets as Liverpool are knocked out of the EFL Cup by Southampton
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Liverpool were knocked out by Southampton the EFL Cup
The 1-0 defeat means Liverpool have won just once since beating Manchester City last month and Verheijen believes their struggles are down to Klopp overtraining his squad.
He wrote on Twitter: “Why are so many people surprised about Liverpool fading in second half of season? It was predicted over and over again during pre-season.
“Liverpool manager Klopp has run his players into the ground during pre-season. Consequently, players cannot perform during an entire season.
Raymond Verheijen reckons Jurgen Klopp has worked his players too hard
“When the Liverpool dip was predicted last August the fans were laughing because Liverpool was winning. But are they still laughing now?
“Liverpool is not even playing in Europe. Just imagine how squeezed the LFC players would have been if they had played CL or EL this season.
“The secret of 'pre-season periodisation' is to develop top fit players while maintaining rather than losing freshness. Quality over quantity.
Raymond Verheijen is known for his criticism of managers
“Most people in football have opinions on hindsight. Liverpool crumbling in 2nd half of season was already predicted multiple times in August.
“Overall, Klopp is one of the best managers in the world. But he clearly has some flaws in his pre-season training methods. Raise your bar!
“After a few seasons the Dortmund players were totally squeezed by Klopp: many muscle injuries, several ACL injuries & relegation problems.”