Capdeville dropped his first set to Serbian Ilia Bozoljac 4-6 but retrenched, taking the next two 6-3, 6-0 to move on.
Hernych won his first set against Australian Nathan Healey 6-3 and was tied 1-1 in the second when Healey quit with a left rib injury. Hernych won't have it so easy next time out -- he next faces world No. 1 Marat Safin.
Robin Haase of the Netherlands defeated Britain's Alex Bogdanovic 6-4, 6-2, while Russian Evgeny Korolev defeated Brazilian Ricardo Mello 6-4, 6-4. Russian Igor Kunitsyn beat France's Sebastien Grosjean 6-7 (3-7), 6-4, 6-3, while Colombian Alejandro Falla downed American Robert Kendrick 3-6, 6-2, 7-5.
This week's top seed is American Andy Roddick, who won the 2001 and 2005 Legg Mason.