Bayern Munich coach Jupp Heynckes said his side took a significant step toward the Bundesliga title after its 3-0 win at Mainz 05 opened up a 14-point lead at the top of the table.

Croatia striker Mario Mandzukic scored twice as Bayern made its superior possession count at fifth-placed Mainz on Saturday.

"We prepared extremely thoroughly, that was a very important victory on the road to the title," said Heynckes, after his side picked up its 16th win from 20 league matches.

With second-placed Bayer Leverkusen hosting defending champion and third-placed Borussia Dortmund on Sunday, Bayern could finish the weekend with 14-point cushion intact.

Midfielder Thomas Mueller gave Bayern a first-half lead before Mandzukic showed why he is keeping German international Mario Gomez on the Bayern bench with a crisp header and shot to become the league's top scorer with 14 goals from 18 games.

After drilling home his shot on 50 minutes, after good work by leftback David Alaba and France winger Franck Ribery, Mandzukic headed home Philipp Lahm's cross seven minutes later as the Croat claimed his fifth goal in three games.

"We knew it wouldn't be easy and we prepared very thoroughly," said Heynckes after Bayern lost two of its past three trips to Mainz's Coface Arena.

"The team put our plan into action really well."

Mueller said his opening goal, just before the halftime break, had settled a few nerves.

"We're pleased about winning a difficult away game in Mainz, but we knew it was going to be hard work," said the Germany star, who is in the squad to play France next Wednesday in Paris.

"In the first half, Mainz were just what you expect of them at home, plenty of bite, very aggressive and tricky.

"Scoring the opening goal was definitely important.

"We were on hand when Mainz gave us the chance. We set off well into the second half, and that was basically that. It was a good day."

After his two goals put him top of the Bundesliga's goal-scoring charts, Mandzukic said he was just pleased to pick up three more points.

"We're doing what we did so well in the first half of the season. We're playing as a team, we go out onto the field and fight, and we know we have the quality," he said.