The former Real Madrid midfielder believes Chelsea's Champions League win in 2012 means no team can be ruled out of the running for the trophy heading into the last 16Galatasaray midfielder Hamit Altintop has called on his side not to underestimate Champions League opponents Schalke when the pair meet in the last 16 on Wednesday.
The Turkey international will be up against his former team and does not believe the German side's poor form should be a factor, citing Chelsea's surprise triumph in 2012.
"This game against Schalke is very special to me as I spent four years at Schalke and played my first Champions League match there," he told GSTV.
"Despite their poor performance in the Bundesliga, Schalke finished top of their Champions League group.
"We must not become complacent, last season Chelsea finished sixth in the league but won the Champions League."
The match will see Wesley Sneijder and Didier Drogba make their European bows for Fatih Terim's side, and Altintop believes having the pair at their disposal will help the team move forward.
He continued: "Drogba and Sneijder are world-class players. It's a huge advantage to have them playing on our team and it raises the profile of Galatasaray in the world."
The 30-year-old also revealed that playing the first match of the tie at the Turk Telecom Arena will give his side an advantage as they look to build a big lead before visiting Gelsenkirchen.
"Playing the first game at home is an advantage in my opinion. With the help of our supporters we hope to go into the second leg with a comfortable advantage," he continued.
"This is an opportunity for us to show our quality, these are the types of game we want to play."