VIENNA, Sept 27 (Reuters) - Former Germany captain Lothar Matthaeus enjoyed his biggest success in a fledgling career as coach on Thursday when his struggling Rapid Vienna team routed Partizan Belgrade to reach the second round of the UEFA Cup.

Rapid, whom Matthaeus joined as sports director earlier this month, beat the Yugoslavs 5-1 for an aggregate win of 5-2.

Roman Wallner put Rapid ahead in the 11th minute and Gaston Taument made it 2-0 in the 34th minute. Damir Cakar reduced the deficit in the 58th minute but Wallner restored Rapid's advantage two minutes later. Rene Wagner sealed the rout with goals in the 65th and 71st minutes.

'This is a sensational win in the European Cup. Partizan have been playing well,' a visibly relieved Matthaeus said after the match. 'I've only been doing my job - trying to convert what we can do in training into a match.'

Matthaeus, captain of the German side which won the World Cup in 1990, left Bayern Munich in March last year. He said he hoped Rapid's strong performance would satisfy the club's frustrated fans.

Rapid's pevious trainer Ernst Dokupil was sacked last month after weeks of violent scenes at matches as fans vented their anger over the club's poor performance.