Claudio Pizarro insists Chelsea 'have to win' their UEFA Champions League match at home to Schalke on Wednesday night.
"With these games you can qualify for the next phase, so it's very important to win the games at home," he told the club's official website.
"It will be a very difficult game for us, but we're at home so we have to win."
The Peru international has identified a number of key threats in the Schalke squad, and has earmarked a number of his fellow South Americans for particular attention.
"They have some very good players - a strong defence with Mladen Krstajic and (Marcelo) Bordon, good players - and the strikers are good, too.
"Everybody knows (Kevin) Kuranyi from the German national team.
"Bordon is from Brazil and Dario Rodriguez and Gustavo Varela are from Uruguay. I don't know if he's playing but Varela is a dribbler - he plays down the right and can do good things.
"Rodriquez and Bordon are both very tough guys at the back."