Mainz German defender #16 Stefan Bell, Mainz Dutch defender #03 Sepp van den Berg and Bayer Leverkusen s Czech forward #23 Adam Hlozek vie for the ball during the German first division Bundesliga football match Mainz 05 v Bayer 04 Leverkusen in Mainz, western Germany, on September 30, 2023. AFP
Leverkusen, who dropped their only points in the league this season in a 2-2 draw at Bayern, took the lead after 18 minutes as wing-back Jeremie Frimpong forced Mainz defender Sepp van den Berg into an own goal.
Dead-ball specialist Alejandro Grimaldo doubled Leverkusen's lead with a pinpoint free-kick before Germany winger Jonas Hofmann scored a third to round out the win.
Hofmann, who moved to Leverkusen in the summer having spent seven years at Borussia Moenchengladbach, now has three league goals and three assists in the Bundesliga for his new club.
"It's a lot of fun. Everyone pats you on the shoulder and tells you how nice the football looks," said Hofmann.
Hofmann toasted his team's "extreme potential" after Leverkusen's best start to a league season in their history, but said "it's important to stay humble."
Mainz have just one point and are bottom of the table after six matches.
Union Berlin's poor start to the season continued, losing 1-0 away at promoted Heidenheim thanks to a second-half goal from Jan-Niklas Beste.
Beste's free-kick deflected into the net midway through the second half, consigning Champions League participants Union to their fifth consecutive defeat in all competitions for the first time since 2004.
Surprise package Stuttgart continued their remarkable rise this season, winning 2-0 at Cologne thanks to a brace from Deniz Undav.
Stuttgart, who needed to win a relegation playoff against Hamburg last season to stay in the top division, are now second after six matches.
The game did however mark the first time this season that striker Serhou Guirassy, who had a remarkable 10 goals from five league matches heading into the fixture, failed to get on the scoresheet.
Wolfsburg striker Jonas Wind, another one of this season's early top scorers, continued his strong form in front of goal, scoring a brace to help his team to a 2-0 home win over Eintracht Frankfurt.
Wind now has seven of his team's nine goals in the Bundesliga this season.
Elsewhere, a double from Alassane Plea took Gladbach to their first win of the season, a 3-1 victory away at Bochum.
Florian Neuhaus opened the scoring for the visitors and Plea added two by half-time.
Bochum's Anthony Losilla pulled one back in the second half and had another ruled out in injury time as Gladbach held on to win.
In Saturday's late game, Bayern can re-take top spot in the table with a win away at RB Leipzig.
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