Vote: Which was your favorite rally of the Bogota quarterfinals?

Another day, another selection of wild rides and clay-court creativity at the Copa Colsanitas Zurich. All four quarterfinals went to three sets, but which was your favorite of these shots?

Irina Bara and Sara Errani's tilt was a duel of the drop shots as both players showed off their finesse throughout. Of the plethora throughout the match, Bara impressed the most with this -- not least due to the geometric point construction as well as the elegance of its execution. A deep, chopped defensive forehand was followed by a shorter, angled mid-court slice to pull Errani off balance, and only then finished off with the forehand drop.

A few points later, Bara had been pushed way out of court by a heavy Errani forehand -- but somehow turned it into a ridiculous backhand winner that landed squarely on the line. "She hasn't made it, has she?" wondered the commentator as Errani rubbed the mark out in acknowledgement of its accuracy. "An impossible shot, really."

Deep into the third set, Errani's creativity came to the fore. An underarm serve caught Bara by surprise, but the Italian still had to hare forward to retrieve her drop shot response and then cover the backhand volley at net.

Camila Osorio responded to Tatjana Maria's awkward short slice by loading her forehand with so much spin that it bounced sideways and caused gasps in the audience. But this is territory Maria has made her own, and the German simply ramped up the junk. Osorio was right there, but could do nothing except flail as the ball fizzed off the clay and away from her racquet.

Laura Siegemund is no stranger to the drop shot. But to try one from that position, pushed almost off the court by a heavy Marie Bouzkova return? And to cut it for a clean winner? "What an extraordinary shot," the commentator marvelled.

As the match reached its climax after nearly three hours, Bouzkova's indefatigable speed came into its own. The Czech reached her first match point after haring across the court to deny Siegemund what had seemed to be a simple putaway, finding the backhand pass instead.

Bouzkova didn't convert in that game, but kept plugging away. In the next, it wasn't just her movement to track Siegemund's drop shot that was impressive, but her reflexes at net as she dived to her left to find a volley winner at full stretch.