Angelique Kerber made short work of Carla Suarez Navarro to reach the Stuttgart Open semi-finals, while Agnieszka Radwanska again proved too good for Karolina Pliskova.
Defending champion Kerber has struggled for consistency since winning the Australian Open in January, but showed signs of her top form with semi-final runs in Miami and Charleston in her past two WTA events.
And the second seed was a class above Suarez Navarro on the German clay as the home favourite romped to a 6-2 6-4 victory in one hour and 14 minutes.
Kerber regularly attacked Suarez Navarro's serve and the seventh seed, who beat Kerber at the same event in 2014, was broken on four occasions.
Next up for Kerber is fifth seed Petra Kvitova, who held off a Garbine Muguruza fightback to record a 6-1 3-6 6-0 victory and earn a first semi-final of 2016.
On the other side of the draw, top seed Agnieszka Radwanska extended her fine head-to-head record over Pliskova in a 6-2 7-6 (10-8) victory.
Radwanska had beaten Pliskova in their five previous contests without a dropping a set and the Pole fought back from 4-2 down in the second to extend a fine record.
Qualifier Laura Siegemund continued her dream week with a 6-1 6-4 victory over Roberta Vinci, sealing a first WTA semi-final of her career.