Tomas Ujfalusi believes Czech Republic will need to be at their best to take anything from their Euro 2008 clash with Portugal.
The Czechs face Luiz Felipe Scolari's men in their second Group A fixture on Wednesday well aware of the attacking threat possessed by their opponents.
Both sides got off to a winning start in their opening fixtures, but Atletico Madrid ace Ujfalusi is all too aware that the Czechs could be on the wrong end of hiding in their next outing if they fail to nullify the threat of Cristiano Ronaldo and co.
"We are well aware that their attackers are very strong, and not just one or two," said the defender.
"They have many fast and dangerous players and we'll have to be very careful and attentive.
"Our defence will have to be impeccable."
Karel Bruckner's side made hard work of securing a 1-0 win against co-hosts Switzerland on Saturday and admits that his players must be more creative in midweek if they are to threaten a Portugal side which cruised to a 2-0 victory over Turkey.
"The last 10 minutes of the Switzerland match were also a problem," he said.
"We should have kept control of the ball more effectively."
Three points for either side on Wednesday would book their place in the quarter-finals and allow them the opportunity to rest key men in their final group games.