Pep Guardiola said Bayern Munich "deserved to lose" after suffering their first Bundesliga defeat of the season at Wolfsburg on Friday night.
Bayern's bid for an undefeated season ended in their 18th game and first after the league's month-long break.
"Congratulations to Wolfsburg, they did really well," Guardiola said. "We deserved to lose.
"Wolfsburg were better and scored their goals at just the right time. We need to analyse what's happened and focus on the next game."
It was a forgettable return to action for goalkeeper Manuel Neuer, who spent part of his time away from the team at the Ballon d'Or ceremony, where he finished third behind Cristiano Ronaldo and Lionel Messi.
Wolfsburg put four goals past Neuer -- the same amount Bayern allowed in total during the season's first half.
"Obviously it's not a good restart for us. We expected a different outcome and went out there looking for it too," Neuer said. "It's not a catastrophe, but we know we still have a lot to do."
Bayern only have three days to recover until they host Schalke on Tuesday, but Neuer said the fixture list could be a hidden blessing.
"We have to put it behind us and look forward," he said. "A midweek game is just what we need right now. It would be bad if we were having to wait eight days for the next match. We have to turn it around from here on in."
Second-place Wolfsburg closed the gap at the top to eight points, and Bayern defender Jerome Boateng suggested his team should use the defeat as a sign that they can not coast to the finish line.
"It's simple -- we played really badly. It might be good that it's happened to us today because it's a wake-up call," Boateng said. "We can't afford another performance like that. We weren't aggressive and gave away possession far too easily.
"We have to take a good, long look at ourselves. We all know we'll need a vast improvement against Schalke if we're to make amends for this."
Bas Dost led the way for Wolfsburg with two goals, with his second on a volley just before halftime being particularly impressive.
"We waited for our chances and hit them at just the right time," Dost said. "I was a bit lucky with my second goal. We saw it through to the end brilliantly after halftime."