Pella stuns Querrey as Kyrgios prevails in Houston
Sam Querrey was eliminated by Guido Pella but fellow seed Nick Kyrgios moved through to the quarter-finals of the US Men's Clay Court Championships.
American second seed Querrey lost 2-6 7-6 (7-4) 7-6 (7-3) against Pella in Houston on Wednesday.
A two-time finalist in 2010 and 2015, Querrey won the opening set and looked in control of the last-16 clash but Pella rallied to win back-to-back tie-breaks after more than two hours.
Argentina's Pella will meet Australian Open quarter-finalist Tennys Sandgren in the last eight of the ATP Tour tournament.
Sandgren – the eighth seed – accounted for another Argentinian Nicolas Kicker 6-2 7-6 (7-3).
Australian star Kyrgios, meanwhile, battled back to beat Bjorn Fratangelo 6-7 (2-7) 6-1 6-2.
Kyrgios made a slow start in his opening match but the fourth seed recovered to outlast the talented American.
Next up for Kyrgios is big-serving Croatian Ivo Karlovic, who defeated Denis Kudla 7-5 7-5.