Portugal boss Roberto Martinez has insisted that his side will have to be at their best to overcome Slovakia in Friday evening's Euro 2024 qualification fixture.

The Iberian side have been excellent in Group J thus far, recording six wins from six matches, which has left them at the top of the section on 18 points, five clear of second-placed Slovakia.

Portugal would book their spot at next summer's European Championship if they overcome Slovakia, while a draw would be enough if Luxembourg lose to Iceland.

Martinez's side were 1-0 winners in the reverse match last month, with Bruno Fernandes netting the only goal of the contest, but the head coach has admitted that his team struggled for stages of the game in Bratislava.

"There are no easy games and that's very clear. We won six games because the players had an exceptional attitude and commitment," Martinez told reporters ahead of the contest.

"That gives them a basis for them to show their talent. We know that individually we have players at a different level to the other teams.

"I think it's important to say that Slovakia was better than us in that first half [of the away game]. It's not that we didn't play well, but Slovakia were very aggressive.

"We struggled a little and in the second half we were better. What we're going to see [from Slovakia tonight] is a very well-organised side."

Fernandes, meanwhile, branded Slovakia "a very intense team", with the Manchester United attacker aware of the size of the task facing his national side on Friday.

"My aim is to help the team however I can with goals, assists, performances or just support. The work we've done has been reflected in the performances and the way we help each other," he told reporters.

"Then after that you can see the quality of the players and what they do on the pitch. They are a very intense team, with players who like to have a lot of the ball. Without the ball, they are very organised.

"Tactically, it is very difficult to penetrates paces against them, something we do a lot in the national team. That was one of the difficulties we had there. They can cause us problems on the counter."

Martinez's biggest decision in terms of his team selection will seemingly come at centre-forward, as 38-year-old Cristiano Ronaldo is back from a suspension, but Goncalo Ramos scored twice in the team's 9-0 victory over Luxembourg last time out.