Bundesliga Preview: Early pacesetters look to reel in Bayern
The three Bundesliga sides with 100 per cent records can all overtake league leaders Bayern Munich this weekend.
Pep Guardiola's men dropped their first points of the season against Freiburg on Tuesday, and the trio of sides on nine points - Borussia Dortmund, Leverkusen and Mainz - will all be looking to take advantage.
Dortmund travel to Eintracht Frankfurt on Sunday, with the hosts having picking up their first points of the campaign last time out against rock-bottom Eintracht Braunschweig.
Jurgen Klopp's charges have conceded just one goal in their three-game winning run as they look to go one better than last term's second-place finish.
Dortmund's last game brought a 1-0 victory against Werder Bremen and, despite an inability to convert all their chances, the 46-year-old is pleased with his side's start to the campaign.
"If you have nine points from three games, and poor finishing is the only point of criticism, then I think I can handle it," he told the club's official website.
Leverkusen are another side to have won all their games, with an in-form Sidney Sam helping his team to a 4-2 victory over Borussia Monchengladbach with a double in their last outing.
Sami Hyypia's men will face a Schalke side buoyed by their UEFA Champions League progression and the news that striker Adam Szalai will not require surgery on a hand injury.
Fourth-place Mainz will look to the Bundesliga's leading scorer Nicolai Muller to help continue their winning streak against Hannover on the road.
Muller has netted four times so far; half the total he achieved in the whole of last season.
Hannover, managed by Mirko Slomka, have enjoyed a mixed start to their league campaign, suffering defeat against Borussia Monchengladbach either side of victories versus Wolfsburg and Schalke.
Hertha Berlin have made a strong start on their return to the top flight and will look to build on their win over Hamburg when they face Wolfsburg.
At the foot of the table, Braunschweig can pick up their first points of the season against Hamburg, a side just three places above them in the table.
Neither side have picked up a win yet, with Thorsten Fink's men shipping six goals in their last two Bundesliga matches.
Stuttgart are also without a win and sit in 17th. They face the league's top scorers Hoffenheim, who have scored 10 goals so far this season.
Sixth-place Werder Bremen will look to bounce back from their narrow defeat to Borussia Dortmund when they face Monchengladbach.
Robin Dutt's side have conceded just once this season and have been boosted by the return to training of Lukas Schmitz following a foot injury.
"What's important is that we have only conceded one goal in three matches," Schmitz told the club's official website.
"You can see the handprint of Robin Dutt, who said from the first day on that we have to have a strong order and play well in the back first.
"That has worked really well thus far and I think if we can do that throughout the whole season, it would be the foundation for a good season."
The other game of the Bundesliga weekend sees a mid-table battle between Nuremberg and Augsburg.