Mendes, 30, is preparing for his first Champions League match since he lifted the trophy with Porto in 2004, with the Light Blues today travelling to Germany for tomorrow night's Group G opener.

Mendes has been on the phone to fellow Portugal international Fernando Meira, who spent six seasons with Stuttgart, playing against Rangers two seasons ago in the group phase.

The two men came through the ranks together at Vitoria Guimaraes and have remained close.

Mendes told his club's official website, www.rangers.co.uk: "Fernando is my best friend so I have been in touch with him to find out what they are all about.

"We know that they are a strong side and he has told me the players to look out for.

"They have lost Mario Gomez, who was an important striker for them but they are still a strong outfit so we know it will be a tough match for us."

Rangers dropped their first Clydesdale Bank Premier League points of the season on Saturday when they were held to a goalless draw at Motherwell.

Mendes added: "It will be a different game in Stuttgart. We have to get our heads up after the disappointment of the Motherwell match and I'm sure we will.

"It's going to be a completely different environment and for me it will be great to be back in the Champions league."

Mendes tipped new team-mate Jerome Rothen to make a real impact tomorrow night.

The pair squared off at the the 2004 Champions League final when the latter was at Monaco.

Mendes said: "Jerome is a very good player; it was only his first game in Scotland last weekend so it will take him time to get used to it.

"However, he has great experience in Europe so the Stuttgart game will not be a problem for him.

"Of course we faced each other in the 2004 Champions League final when I was with Porto and he was with Monaco and then we saw each other again in the summer when we played Paris St Germain in the Emirates Tournament.

"I reckon he is a good signing for us because he offers good delivery from the left side and he can be very effective from set pieces.

"These qualities could be very important against Stuttgart."