Arsenal manager Arsene Wenger has claimed that the demands of the Premier League can negatively affect English clubs' campaigns in European competitions.
The Gunners will take on Olympiacos at the Emirates this evening in a Group F clash.
The North London outfit are yet to pick up any points in the elite competition having suffered a shock 2-1 defeat to Dinamo Zagreb earlier this month.
Ahead of the match, Wenger, whose side claimed a 5-2 victory over Leicester City on Saturday, showed concern that the intensity of the top flight in England damages preparations for European matches.
"These teams dominate their leagues," Wenger told reporters. "Olympiacos won comfortably on Saturday, they were safe after 20 minutes, when we were in a high-intensity game at Leicester.
"Mentally you cannot ease off before a Champions League game, as some others can. For example, Dinamo Zagreb played on Saturday and they took three players off at half-time. I cannot do that at Leicester.
"For sure the Premier League is demanding and consuming energy wise - mentally more than physically."
After tonight's match, Arsenal's next two Champions League fixtures are back-to-back games against Bundesliga giants Bayern Munich.
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