Jorge Sampaoli says Sevilla must rediscover their "football instinct" if they are to avoid crashing out of the Champions League after an underwhelming draw at home to Leganes.
A second draw in as many games leaves Sevilla lagging behind Real Madrid and Barcelona in the race for LaLiga.
Sevilla go to the King Power Stadium on Tuesday with a 2-1 lead from the first leg, which was Claudio Ranieri's last game in charge of the Premier League champions.
Since the Italian's dismissal, Leicester have beaten Liverpool and Hull City 3-1 on home turf and they will be well-rested after a weekend without domestic duties.
"If we give this performance again, we will have a lot to worry about in the Champions League," Sampaoli told a news conference after Saturday's draw.
"These games, where your opponents punish you for each error, are much tougher and if we cannot improve our control of matches then Tuesday's game will be very difficult.
"With these two draws, we have not lost for eight matches, but we must be more culpable for our own actions during the 90 minutes.
"We have lost our footballing instinct and it's preventing us from controlling match situations.
"The solution is to continue to be pragmatic, [Leicester] are very fast and anxious to win whereas [Leganes] were very orderly and imposed themselves on us.
"We have to think about two different teams, two different but important matches, and prepare our best performances."