Sevilla coach Unai Emery feels his side have little margin for error as they face the attacking power of Manchester City again in the Champions League.
The Spanish side performed impressively at the Etihad Stadium a fortnight ago but were stung by an injury-time goal from Kevin De Bruyne as City snatched a last-gasp 2-1 win.
The result left last year's Europa League winners third in Group D, three points behind City and four behind leaders Juventus midway through the first stage.
Emery says his side can ill afford a repeat and knows defence could be key in Tuesday's return clash against the Premier League outfit at the Ramon Sanchez Pizjuan Stadium.
Emery said: "This could be decisive in terms of what happens to us in the competition. If we want to get through to the next phase we have to be brave tomorrow and give our best.
"We need to play well, be solid. We know they are going to pose a great threat to us. They are a team that are very well drilled.
"We have to work hard, defend well and be very solid at the back. That is what is going to help us progress in this tournament and this season in general."
City are without leading scorer Sergio Aguero and the game also seems likely to come too soon for Spain playmaker David Silva.
But with De Bruyne, Raheem Sterling, Jesus Navas and Wilfried Bony, City still boast attacking talent worth around a combined £140million.
Asked at his pre-match press conference if he was worried about this, Emery said: "We are concerned and we are focused but worried is perhaps too strong a word.
"We know what we have to do in terms of getting a result for ourselves. We are looking to drive forward, play with intensity and play quickly.
"We are a lot stronger defensively at home. So we need to make the most of that and we need to give them a feel of how difficult it is to come to our stadium and play against us."
Sevilla know all about Navas. The 29-year-old winger came through the club's academy system and made 393 appearances for the first team, scoring 34 goals and helping them win the UEFA Cup twice, before joining City in 2013.
Emery said: "Jesus Navas is coming home, but he is playing against us, unfortunately. He is obviously a competitive player and I am sure he will be happy and excited to be returning to the Ramon Sanchez Pizjuan Stadium.
"He will want make the most of the spectacle tomorrow but hopefully we will face the worst version of him. I wish the best for him individually but not tomorrow."
Source: PA
