London - Everton manager Roberto Martinez fears his side's Europa League exertions could leave them with an empty tank as they seek to end a dismal run of domestic form.
A 2-0 defeat by Stoke City in the Premier League on Wednesday left Everton in 14th place, six points above the relegation zone.
While they have reached the last 16 of the Europa League, a competition Martinez has made no secret of prioritising with a Champions League spot the carrot for the winner, they have managed only one win in their last 10 Premier League games.
"It's disappointing as it has been a really tough two weeks. We showed that lack of cutting edge," Martinez, who was relegated with Wigan Athletic two years ago, told the BBC.
"I did feel that as a team we showed we had played a number of matches in a short period of time.
"The Europa League campaign is a bit obvious at the moment as it is a lot of games to play in a short period but as a club that is what we want, to play in Europe.
"The concern is a huge moment in the season, we have 10 games and we will treat them as finals.
"The desire and wanting for the result was there but the legs couldn't get there."
Stoke won with goals from Victor Moses and Mame Biram Diouf to leave Everton with 28 points from 28 games, their worst haul in the Premier League era.
Everton face Dynamo Kiev in the Europa League.