Bayern Munich coach Louis van Gaal has said his side must stop giving away possession ahead of their last 16 match against holders Inter Milan in the Champions League on Wednesday.
The defending Bundesliga champions remain 13 points behind leaders Borussia Dortmund, but gave themselves a pre-Champions League boost with a 3-1 win at title-rivals Mainz on Saturday.
Goals by Germany stars Bastian Schweinsteiger and Thomas Mueller put Bayern in control before hot-shot Mario Gomez netted his 18th goal in 21 league matches with time almost up.
Tunisia striker Sami Allagui netted a late consolation goal for the hosts.
Ahead of Wednesday's Champions League match at the Stadio Giuseppe Meazza and next Saturday's crucial German league clash at home to Dortmund, Van Gaal said victory had been 'crucial' but there was still improvements to be made.
"That was a crucial victory, I'm very happy, because it's always difficult against Mainz, although we did miss a lot of chances," said the Dutchman.
"We've played very well, created chance after chance, and scored three goals.
"But we gave the ball away unnecessarily far too often, we were very careless in the final quarter of the field.
"We know that, and we'll improve. But overall, I'm very satisfied."
With a shocking 3-2 league defeat at Cologne their only reverse in the last 10 games, Bayern are on a roll and goal-scorer Gomez said that must continue in Milan.
"We can't afford any more slip-ups, we need to keep this run going," he said.
"Mainz were clearly up for it, so the early goal was very important.
"All that counts for us now is to win."
Mueller agreed with his coach that the German champions can't afford to give possession away cheaply to the Italians.
"We lost possession too cheaply when we were going forward, we made life much too difficult for ourselves," said the 21-year-old.
"Mainz also looked good when they attacked, we should have been much smarter about keeping possession.
"But otherwise, we counter-attacked well and finished off our chances, so it was a deserved win."