Arsenal boss Arsene Wenger admits they must be more ruthless if they're to do better this season.

The Gunners claimed a second consecutive fourth-placed Premiership finish last season despite being second only to Manchester United in terms of results against top-10 sides.

"That shows we lost the championship against teams in the bottom half of the table," said Wenger.

"So that is where we will have to be much more efficient this season. We have to be consistent in our mental preparation, in our ruthlessness as well.

"We have a mixture of mental strengths, of potential, but there is also a naivety and sometimes we have not been ruthless enough.

"It is these two ingredients which have to be improved. My squad have outstanding qualities, there are factors in the team which can tell you that this side can be absolutely outstanding.

"But to win trophies you have to be a killer. You have to be everything together - and that is what we are aiming for."