Defending champion David Nalbandian dropped out of the Legg Mason Tennis Classic in Washington DC at the first hurdle as he was defeated by James Blake.
Nalbandian, seeded eighth, never found his rhythm as he lost 6-2 6-4 in the second-round clash.
The Argentinian was the only seed to lose as number 11 John Isner topped Tobias Kamke 6-1 6-3, 13th seed Kevin Anderson rallied to dispatch qualifier Chris Guccione 3-6 6-2 7-6 (7-0) and number 16 Jarkko Nieminen beat Igor Kunitsyn 7-5 6-4, all in second-round clashes.
The rest of today’s action was in the first round, and was highlighted by a lengthy battle between Grigor Dimitrov and Tim Smyczek, which eventually saw Dimitrov come through 4-6 7-6 (7-3) 7-6 (7-3).
Ryan Sweeting beat Alex Bogomolov Jr 6-2 6-4, Flavio Cipolla dispatched Marsel Ilhan 7-5 6-0 and Michael Berrer was a 7-5 6-1 winner over Paolo Lorenzi.
Wildcard Ryan Harrison advanced with a 6-4 1-6 6-1 win over Mischa Zverev, Somdev Devvarman beat Denis Gremelmayr 6-2 6-3 and Tommy Haas beat Amer Delic 6-2 6-3.