Svitolina, Andreescu dumped out of Eastbourne grasscourt event
Kazakhstan's Elena Rybakina upset second seed Svitolina 6-4, 7-6 (7/3) to reach the quarter-finals while Andreescu, seeded third, went down 6-3, 6-3 to Anett Kontaveit of Estonia at the Wimbledon warm-up event.
Svitolina held game point to edge 5-4 ahead in the first set but Rybakina found three stunning forehand winners to snatch the crucial break and take the lead instead.
The world number 21 maintained her advantage, breaking early in the second set but missed an opportunity to take a 5-2 double-break lead and Ukraine's Svitolina forced a tie-break.
Undaunted, Rybakina refocused and a series of emphatic serves and backhands enabled her to dominate, sealing her third match point with a service winner.
Kontaveit breezed past Canada's Andreescu, converting six of her eight break points against the 2019 US Open champion.
But top seed Aryna Sabalenka was untroubled by any thoughts of an upset as she stormed past Alison Riske, 6-1, 6-4.
Jelena Ostapenko came from a set and a break down to beat Birmingham champion Ons Jabeur 5-7, 6-4, 6-3 and Anastasija Sevastova saw off American teenager Coco Gauff 4-6, 7-5, 6-2.
In the men's tournament, top seed Gael Monfils lost 6-4, 5-7, 6-4 to Australia's world number 283 Max Purcell.
Monfils came within two points of defeat at 4-5 in the second set, but a crosscourt forehand winner sparked the Frenchman into life.
From 3-5 down in the second set, Monfils won seven straight games before Purcell won five in a row to lead 5-3 in the decider and he calmly closed out the match.
Purcell will next play 2011 champion Andreas Seppi, who defeated Emil Ruusuvuori of Finland 6-2, 6-3.