Mats Hummels believes Toni Kroos' stoppage-time winner against Sweden can kick-start Germany's World Cup campaign, though he recognises the champions have plenty of room for improvement.
Germany emerged from the jaws of elimination to the cusp of the knockout phase thanks to Kroos, whose 95th-minute free-kick lifted Joachim Low's 10-man side to a last-gasp 2-1 victory in Sochi on Saturday.
The holders, who had Jerome Boateng sent off late for a second yellow card, dominated in attack but were vulnerable in defence throughout the Group F showdown at Fisht Stadium.
Star defender Hummels, who missed the crucial fixture due to a neck injury, acknowledged Germany's need to improve ahead of their final game against South Korea, having lost to Mexico in the opening match.
"We were better than Sunday but not as good as we have to be in the next games," Hummels told reporters afterwards. "It will be a different game, a different opponent. We will analyse it. See what we have to do better.
"For our emotional side, it was a very good thing today because you start believing with games like this that you can pull a lot off."
Asked about Kroos' dramatic winner, Hummels said: "Something like this can be a big moment in a tournament but if we lose to South Korea or don't advance, it doesn't mean anything.
"We got a little bit lucky today. We have to show and prove that we can be better."
Hummels was replaced by Antonio Rudiger for the game in the Black Sea resort city, having sustained a neck injury in the lead up to the clash.
"I had a problem in training on Thursday. A big problem," the Bayern Munich centre-back added. "It's healing good since then but the doctor said it was too much of a risk that something very serious could happen. It was very hard for me to accept."
Rudiger deputised in place of Hummels, partnering Boateng at the heart of Germany's defence.
The Chelsea defender and Boateng were often exposed as Germany pushed numbers forward against Sweden.
"It's not that easy but we did it good against a defensive setup," Rudiger said. "We had many chances and in crucial games, you have to take it."
"We gave our all. It's easy for others to say it's easy to play against Sweden but it's not easy because they defend very well," he continued. "We have to look game per game. The next is South Korea and we will give our all."