Daniel Altmaier pulled off a major upset on Tuesday, beating top seeded Alexander Zverev in a battle of German players to qualify for the second round of the Mexican Open. The 27-year-old Altmaier and world's 57th ranked player defeated his countryman for the first time in three tries in 2:26 hours and will play Miomir Kecmanovic next. Zverev, sixth in the ATP rankings, lost a seven-match winning streak against German players. His previous loss against one was in 2019, when he fell to Dustin Brow, in Stuttgart.