"A few things will happen I am pretty sure", Goal.com quotes the German as saying following the 2-0 win over Wigan Athletic.
As Liverpool go into the season with only two quality center-backs--Joel Matip and Mamadou Sakho--that could be labelled as reliable, it would be an absolute risk to keep it that way.
"I can talk of Mario because that one is obvious and I have spoken to him about this", said Klopp.
While Allen's global displays may have enhanced his club prospects, goalkeeper Loris Karius has rejected the chance to play for Germany at the Rio Olympics this summer in a bid to become Klopp's number one.
"It's the foot he had problems with in the past and then he had a little bit of pain when pre-season started because of the intensity".
Liverpool's squad could be trimmed down even more this summer as Jurgen Klopp looks to offload a number of players. It's not too seriously, hopefully.
He said: "Everyone expects big names and a big improvement because of big names and if you don't know the players it's like 'what are we doing? what are they doing?' We decided Joel but for him it was a little bit too much today".
None of the four players Liverpool has signed, Sadio Mane, Joel Matip, Marko Grujic and Loris Karius, are household names, but Mane comes the closest to reaching that status.
Klopp is quoted as saying by the Daily Express: "If you want to have proof of the different ways that football can work you only have to look at the European Championships".
Second-half substitutes Danny Ings and Ben Woodburn were on target for Klopp's side who finished the match with 10 men as a result of Matip's departure.
Croatia worldwide Lovren said the gruelling sessions were crucial for Liverpool, expecting similar when their campaign proper begins at Arsenal on August 14. They also saw our games on television.
That is the verdict of defender Dejan Lovren, who says the brutal training sessions are necessary to get their squad in shape for a campaign that could see as many as seven sides with a genuine chance of winning the title. With tons of experience, he could become a teacher to the younger players, especially the highly talented 19-year-old, Joe Gomez.