Massu, Chela in clay-court quarterfinals

HOUSTON, April 8 (UPI) -- Nicolas Massu and Juan Ignacio Chela both reached the quarterfinals Wednesday at the rain-marred U.S. Men's Clay Court Championship.

Massu needed three hours, 25 minutes to survive against Ryan Sweeting 6-7 (5-7), 7-6 (7-3), 6-4 at the River Oaks Country Club.

Chela ousted No. 7 seed Eduardo Schwank 6-1, 6-7 (5-7), 6-1.

Rain forced the postponement of two second-round matches -- Lleyton Hewitt vs. Somdev Devvarman and Sam Querrey vs. Blaz Kavcic.

Massu will meet the Querrey-Kavcic winner. Chela will take on the survivor of the Hewitt-Devvarman match.