Frank De Boer heavily criticised on Twitter by Raymond Verheijen

The Ajax boss and Newcastle United manager target has been slammed for his training tactics.

Newcastle United confirmed earlier this week that temporary boss John Carver will remain in charge of first-team affairs until the end of the season. He has been in charge since Alan Pardew left to take over at Crystal Palace.

But come the end of the campaign Newcastle will be looking to appoint a permanent boss. One name that has been frequently named as a favourite for the role is Dutch coach Frank De Boer.

Last week the Ajax manager confirmed he could be interested in the role. He was quoted by The Guardian as saying:

“I have everything open.

“But I will be ready that’s for sure. I only said if they asked I don’t go now because I am with Ajax and I don’t want to go halfway through a season while also stepping into a team that are already halfway too. So, for me, if there will be a chance it is always in the new season.”

De Boer has an excellent record on paper. He has led Ajax to four Eredivisie titles in a row and is therefore rightly considered one of Europe's best young managers.

But one man is not impressed with his coaching. Ajax are struggling to keep up with PSV Eindhoven in the race for the Eredivisie. Ajax recently went to a winter break training camp in Qatar, which is where the criticism from renowned fitness coach Raymond Verheijen.

His fellow Dutchman, who was Gary Speed's assistant manager for the Welsh national team from 2011 into 2012 launched a Twitter tirade against the Ajax boss - who he would seemingly not give the thumbs up to get the Newcastle job.

Here is a selection of his Tweets:

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