Liverpool manager Jurgen Klopp is "not too happy" with the club's fixture congestion over the festive period.
The Reds have less than 48 hours between matches against Manchester City and Sunderland after the games were rescheduled for television coverage.
The home match against City is now at 17:30 GMT on 31 December - and kick-off at Sunderland is 15:00 on 2 January.
Klopp, 49, said he "cannot believe" the turnaround time, adding: "How do you prepare a team for this?"
The German, who has guided Liverpool to fourth in the Premier League after seven games, said: "Do you say 'only 50% against City because we have Sunderland on Monday?'"
Liverpool's match against Stoke, which was scheduled for 26 December, has also been moved - to 17:15 the following day.
"I understand tradition - I would never say Boxing Day is not a good idea as I love it and I have absolutely no problem," Klopp added.
"I learn more and more about this league and maybe I have to ask someone if we can ask if there will be another time for us at Sunderland.
"Everyone is asking why England is not too successful in big tournaments.
"Ask what other big countries are doing at this time - they have their legs on the sofa and are watching English football."
'This Dutch guy'
Klopp referenced criticism from Dutch coach Raymond Verheijen who questioned his training methods last season, saying they cause injuries.
Regarding the fixture pile-up, Klopp said: "You will sit there and say, 'you didn't perform too well, how did this happen?' Or, 'injuries - oh?' And then this Dutch guy says 'the training is not too good'."
Verheijen, a former Wales assistant coach, responded on social media saying Klopp had "caused 20 hamstring injuries in 10 months" as Liverpool manager and "keeps blaming external factors for injuries".
He later tweeted: "The press conference by Liverpool coach Klopp is a great lesson for all coaches. Never let 'a Dutch guy' or anyone else get under your skin."