Four of the eight second-round confrontations had been scheduled, but only one got under way and it was halted by the rains with Paolo Lorenzi holding a 3-2 lead over Flavio Cipolla in the first set.
John Isner, last year's runner up, also had his meeting with Jack Sock postponed for 24 hours.
Although the second round was pushed back by the rain, two matches were completed early in the day that completed the first round.
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