Greece secured a first ever victory over Germany, winning 1-0 in Augsburg on Sunday to hand Jurgen Klopp his first defeat as head coach, with Dimitrios Kourbelis's second-half strike settling a limp Nations League contest at Klopp's first home game in charge.
Kourbelis broke the deadlock in the 74th minute, latching onto a pass from Arsenal winger Christos Tzolis before drilling a low shot that deflected off captain Joshua Kimmich's foot and beat goalkeeper Alexander Nubel into the bottom corner.
Greece had gone close moments earlier when Fotis Ioannidis blazed wide with only Nubel to beat, while at the other end Hoffenheim's Bambase Conte, a surprise inclusion in Klopp's squad, forced a smart low save from goalkeeper Konstantinos Tzolakis after the break.
Germany dominated possession throughout, with winger Karim Adeyemi their most threatening outlet after an improved display following his struggles against the Netherlands, though his best effort on the counter sailed over the crossbar before half time.
The WWK Arena atmosphere often resembled a Greek home game, with thousands of supporters among the estimated 500,000 people of Greek heritage living in Germany turning out to cheer on their side throughout Sunday's contest.
The result leaves Klopp without a win from his first two matches in charge, following a 1-1 draw away to the Netherlands on Thursday, after the 59 year old fielded five changes and included 16 uncapped players across his 44 man squad.
Greece had never previously beaten Germany, losing seven and drawing three of their meetings since 1960, making Sunday's result the most significant in the history of a fixture long dominated by the four time World Cup winners.
Greece now lead the group on six points, with the Netherlands second on four, Germany third with just one point, and Serbia bottom without a single point after two rounds of fixtures.
Klopp's rebuilding project, following Germany's last 32 exit at this year's World Cup, continues on October 1 when Serbia visit, before a testing return trip to Greece three days later in search of a first win.