Real Madrid's 100% record could come under serious threat this weekend when they travel to face in-form Sevilla.

And the capital club could be without star player Cristiano Ronaldo.

Madrid's 3-0 victory over Marseille in the Champions League last night was their seventh win in seven domestic and European matches this season, during which they have scored 24 goals and kept five clean sheets.

However, Manuel Pellegrini's side may have a fight on their hands to keep that winning streak going against Sevilla who, since losing to Valencia in their opening match of the season, have rattled off six successive victories.

The Andalusians have only conceded twice during that spell, and in their last two outings - both away from home - have put four goals past both Athletic Bilbao and Rangers.

"If we continue along this line we have a chance of winning any game. We are having a very good season, working hard and playing very well," said Sevilla winger Jesus Navas.

"We only have to focus on working well (against Madrid) and we will have a chance of winning. It's going to be a tough game, the two teams are up both there and we have to go out with the same attitude as always.

"They have very good players, but we have to concentrate on ourselves."

One of Madrid's most influential performers this season may be missing, though, after Ronaldo picked up an ankle knock during the win over Marseille.

The world's most expensive player netted a brace in that match to take his tally to nine for the season in all competitions, but it remains to be seen if he will be fit to travel to Seville.

"We cannot discard him for Sevilla. We have to see how he progresses," said Pellegrini following last night's game.

Madrid and third-placed Sevilla are not the only sides to have enjoyed a superb start to the season however, with Barcelona winning six of their seven matches, having only been held by Inter Milan in the Champions League.

Pep Guardiola's treble winners host Almeria this weekend, a match Barca won 5-0 last season after scoring five times in the opening 36 minutes.

Barca midfielder Xavi, whose side beat Dynamo Kiev 2-0 in midweek, is taking nothing for granted though, pointing out: "Almeria have had the whole week to prepare themselves, they will have been studying us. It will not be an easy game."

Madrid and Barca both sit atop the Primera Division table with a maximum 15 points, while Sevilla are three points back in third.

In fourth place are Real Mallorca and they will attempt to continue their fine start when they travel to Sporting Gijon this weekend.

At the foot of the table two of Spain's leading clubs will be desperately hoping to get their campaigns up and running.

Villarreal, who are second-bottom with just two points, are at home to Espanyol while Atletico Madrid, who are just one point and place better off, host Real Zaragoza having suffered more misery in midweek after losing 2-0 at Champions League opponents Porto.

Bottom club Xerez picked up their first ever Primera Division point with last weekend's draw at Espanyol, and will be trying to build on that - and net their first-ever top-flight goal - when they host Andalusian neighbours Malaga.

Elsewhere, Deportivo La Coruna, Athletic Bilbao and Valencia, who are currently fifth, sixth and seventh in the standings respectively, are away to Tenerife, Real Valladolid and Racing Santander, while Osasuna go to Getafe.