Birmingham City Ladies winger Karen Carney says her side must be more ruthless following their Continental Cup home defeat by Notts County.
Blues are still unbeaten in the FA Women's Super League, sitting top of the table after five matches.
But Sunday's 2-0 Continental Cup reverse leaves them now relying on other results to qualify.
"We've done well in the cup so to lose is disappointing. We have to be more ruthless," she told BBC WM 95.6.
"Clean sheets usually win you games and it was a real smash and grab, but we missed our chances too. That's cup football for you.
"It looks like we've only got one goal now and that's the league."
Blues' first defeat in domestic competitions this summer knocked them off the top of Group Three. And their hopes of booking one of the four semi-final slots are now dependant on them beating Bristol Academy at Damson Park this Sunday, while hoping that Notts fail to win at Yeovil the day before.
If Notts do win, then Blues could still get through as the best of the second-placed teams. But Arsenal, in Group One, could spoil that if they win their last two matches - at home to London Bees on Thursday evening, then at Millwall on Sunday - and maintain their slightly superior goal difference.
"It's between us and Arsenal for the best second place," added Blues boss Dave Parker. "We're on the verge of going out of this cup, but we just have to win our remaining game and see if we can squeeze through."