Azevedo held off his team-mate for the win

Azevedo beat Spanish team-mate Igor Gonzalez de Galdeano, last year's winner, over the 191km route from Ravensburg to Feldberg.

Spain's Isidro Nozal Vega and German Joerg Jaksche came third and fourth, 24 and 25 seconds back.

They completed a strong overall performance from Spanish team ONCE, whose riders filled the top four places.

Azevedo takes over from Switzerland's Gregory Rast at the top of the overall standings, with Gonzalez de Galdeano second four seconds back and Nozal Vega third, 25 seconds behind.

German Jan Ullrich, preparing for the Tour de France with his new Bianchi team, damaged his chances of victory by finishing 18th.

But the German remained upbeat.

He said: "Overall I'm rather satisfied. It's looking pretty good for the Tour de France."

The race ends on Monday in Saarbruecken but could effectively be decided in Sunday's penultimate stage, a 40.7-km individual time trial around Bretten.

In France, Spain's Francisco Mancebo, riding for ibanesto.com team, won the 174km Alps Classic race between Aix-les-Bains and Chambery.

Benoit Salmon was second more than a minute back, while David Millar showed he was clear of his early season injury setbacks with third place overall.

In the Euskal Bizikleta race in Spain, Jose Antonio Pecharroman (Paternina) leads overall from Joseba Beloki (Once) and Francesco Casagrande (Lampre) after Saturday's fourth stage.

1. Jose Azevedo (Por) ONCE 4hrs 49mins 49secs
2. Igor Gonzalez de Galdeano (Spa) ONCE same time
3. Isidro Nozal Vega (Spa) ONCE 24 secs behind
4. Joerg Jaksche (Ger) ONCE 25
5. Michael Rogers (Aus) Quick Step 32
6. Angel Vicioso Arcos (Spa) ONCE 46
7. Patrik Sinkewitz (Ger) Quick Step 48
8. Alexander Vinokourov (Kaz) Team Telekom 52
9. Goeffrey Demeyere (Bel) Vlaanderen 58
10. Davide Rebellin (Ita) Gerolsteiner same time

Leading overall standings:

1. Azevedo 23hrs 58mins 23secs
2. Gonzalez de Galdeano 4 seconds behind
3. Nozal Vega 25
4. Jaksche 35
5. Rogers 42
6. Sinkewitz 58
7. Rebellin 1:08
8. Paolo Savoldelli (Ita) Team Telekom same time
9. Steffen Wesemann (Ger) Team Telekom 1:14
10. Jens Voigt (Ger) Credit Agricole 1:18

Alps Classic result:

1. Francisco Mancebo (SPA) 4hr 54mins 49secs
2. Benoit Salmon (FRA) at 1min 17secs
3. David Millar (GBR) 1:41
4. Patrice Halgand (FRA) 1:53
5. Laurent Dufaux (SWI) 1:53
6. Inigo Chaurreau (SPA) 1:55
7. Pierre Bourquenoud (SWI) 1:57
8. Piotr Wadecki (POL) 2:03
9. Alexandre Botcharov (RUS) 2:08
10. Nicolas Vogondy (FRA) 2:08

Euskal Bizikleta stage 4a results:

1 Francesco Casagrande (Ita) Lampre 1.53.44 (46.1 km/h)
2 David Etxebarria (Spa) Euskaltel-Euskadi 0.02
3 Leonardo Piepoli (Ita) IBanesto.com
4 Haimar Zubeldia (Spa) Euskaltel-Euskadi
5 Jose Antonio Pecharroman (Spa)
Paternina-Costa de Almeria
6 Nacor Burgos (Spa) Colchon Relax-Fuenlabrada 0.06
7 Miguel Martin Perdiguero (Spa) Domina Vacanze-Elitron
8 Joseba Beloki (Spa) ONCE-Eroski
9 Giuseppe Guerini (Ita) Telekom 0.08
10 Inigo Cuesta (Spa) Cofidis

Euskal Bizikleta stage 4b results:

1 Jose Antonio Pecharroman (Spa) Paternina-Costa de Almeria 23.09 (42.76 km/h)
2 Joseba Beloki (Spa) ONCE-Eroski 0.17
3 Haimar Zubeldia (Spa) Euskaltel-Euskadi 0.20
4 Jon Odriozola (Spa) IBanesto.com 0.29
5 Francesco Casagrande (Ita) Lampre 0.44
6 Koldo Gil (Spa) ONCE-Eroski 0.45
7 Alberto Martinez (Spa) Euskaltel-Euskadi 0.55
8 Roberto Laiseka (Spa) Euskaltel-Euskadi 0.57
9 Aitor Kintana (Spa) Labarca 2-Cafe Baque 1.01
10 Marcos Serrano (Spa) ONCE-Eroski 1.03

Leading overall standings:

1 Jose Antonio Pecharroman (Spa) Paternina-Costa de Almeria 15.00.03
2 Joseba Beloki (Spa) ONCE-Eroski 1.05
3 Francesco Casagrande (Ita) Lampre 1.26
4 Haimar Zubeldia (Spa) Euskaltel-Euskadi 1.27
5 Roberto Laiseka (Spa) Euskaltel-Euskadi 2.10
6 Aitor Kintana (Spa) Labarca 2-Cafe Baque 2.14
7 Leonardo Piepoli (Ita) IBanesto.com 2.32
8 I�igo Cuesta (Spa) Cofidis 2.39
9 Giuseppe Guerini (Ita) Telekom 2.42
10 Jos� Luis Arrieta (Spa) IBanesto.com 2.44