Shunsuke Nakamura admits Celtic are not ready for their Champions League game against Manchester United.
United welcome the Scottish champions to Old Trafford tomorrow night and the Japanese midfielder believes the clash has come too soon for a team who only just managed to scrape a win over Aberdeen at the weekend.
'We need to improve as a team before this game because we're not playing well enough for the Champions League,' he told the Scottish Sun.
'The manager has brought in two or three new players and unfortunately we still don't know each other well enough.
'So far this season, I don't think we've been playing well as a team.
'Our last game against Aberdeen brought a win, but we didn't play well. For me, we played too many long balls to [Jan Vennegoor of] Hesselink and that's not good enough for the Champions League.'
Nakamura believes a point from their Champions League opener is the best Celtic can hope for.
He added: 'For this game, we can't go down to Manchester and attack, attack, attack. It's hard to win there so for us it will be vital to defend in this game.
'Right now, I think a draw would be an important result for us.'