Former world No. 1 Hewitt defeated Argentine Eduardo Schwank 6-1, 6-0 and Querrey beat Frenchman Jeremy Chardy 7-6 (12-10), 6-4.
Hewitt, a former Wimbledon champion, won in this tournament in 2000, 2001, 2002 and 2006.
In other action involving seeded players Monday, Spaniard Feliciano Lopez beat American Robert Kendrick 7-6 (7-3), 7-6 (7-3); Frenchman Paul- Henri Mathieu beat Romanian Andrei Pavel 6-4, 7-6 (8-6); Russian Mikhail Youzhny defeated Spaniard Oscar Hernandez 6-4, 6-2; and Spaniard Guillermo Garcia-Lopez trounced Taiwan's Yen-Hsun Lu 6-1, 6-1.
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