Manchester United manager Jose Mourinho has insisted that taking part in the Europa League puts his side at a disadvantage in the Premier League title race.
The Portuguese is also unhappy with league officials for their scheduling of fixtures, hinting that other teams are perhaps given more favourable treatment.
United will compete in Europe's second-tier competition for a second time in three years this season after missing out on the Champions League, beginning their campaign with a difficult test away at Eredivisie outfit Feyenoord.
Speaking to reporters on the eve of the match, Mourinho said: "It is more difficult [to balance the two competitions]. Especially because you have also the chance to play on the Monday, but we did not get that privilege, so when we play Thursday, we were never given a Monday spot, to have one more day.
"We know that we are not going to have any kind of support for that, in fact the week when we play Liverpool, Fenerbahce and Chelsea, the gift was to play Liverpool on the Monday, but the Monday before, not the Monday after.
"We play Liverpool on the Monday (October 17), then we play Fenerbahce on the Thursday (October 20) and then Chelsea on the Sunday (October 23)."
Mourinho has tasted success three times in European competition in the past, having won the Champions League with both Porto and Inter Milan, as well as lifting the UEFA Cup with Porto in 2003.
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