MAINZ, Germany, Sept 30 (Reuters) - Bayer Leverkusen cruised past hapless hosts Mainz 05 3-0 on Saturday to record their best-ever start to a Bundesliga season and take over top spot after six matchdays.

Xabi Alonso's unbeaten team have now won five of their six games for 16 points, more than ever before at this stage of a Bundesliga season.

VfB Stuttgart are a point behind in second place following their 2-0 win at Cologne. Bayern Munich, in fourth on 13, take on RB Leipzig later on Saturday.

Mainz defender Sepp van den Berg put the visitors in front in the 18th minute when he slid in to intercept a cutback but instead pushed the ball into his own net.

There was nothing lucky about Alejandro Grimaldo's 59th-minute free kick which he whipped over the wall and into the top corner.

With Leverkusen keeping up the pressure, it was Germany international Jonas Hofmann six minutes later who thumped in their third goal, leaving Mainz firmly anchored in last place with just one point so far. (Reporting by Karolos Grohmann; editing by Clare Fallon)