Saina saved two game points but Juliane soon roared back into the contest with an elegant cross-court flick at the nets which caught the Indian napping at the forecourt.
In the decider, Saina looked to play more rallies but Juliane matched the Indian and waited for her to commit mistakes. Saina once again started hitting long and wide to allow Juliane to get hold of the lead at 6-4.
Juliane looked at ease and her smashes and aggressive net play left Saina looking for answers as the German went into the breather at 11-5.
After the breather, Juliane found the net and hit long to give Saina a couple of points but the Indian once again failed to get the length of her stokes right as Juliane reached 14-7. Saina tried to keep her cool and tried to push Juliane to make mistakes to slowly narrow the gap to 14-16.
However, a cross court smash, a brilliant net play and another down the line smash helped Juliane to make it 19-14.
What came next was a long rally, which culminated with Saina hitting wide, giving Juliane six match points. Another missed point at the net, and Juliane was celebrating.
Juliane will next take on the winner of world number one Xuerui Li of China and Pui Yin Yip of Hong Kong.