Play was suspended because of rain after just six minutes of action in the final round of the weather-delayed Booz Allen Classic in Potomac, Maryland on Monday.
The scheduled resumption had already been put back by three hours following steady overnight rain at the TPC at Avenel.
American Ben Curtis held an eight-stroke lead at 23-under-par after 11 holes with compatriot Billy Andrade and Ireland's Padraig Harrington his closest challengers on 15-under.
Andrade holed a 27-foot birdie putt at the last to complete a seven-under-par 64 and hold the clubhouse lead.
Curtis, the 2003 British Open champion, did not have enough time to complete the 12th hole but Harrington parred the 14th to stay at 15-under before play was again suspended.
The weather problems at the Booz Allen Classic had already forced a change in Monday's British Open international qualifier being held at nearby Congressional Country Club.
The US leg of final international qualifying for the third major championship of the year has been reduced from 36 holes to 18, with a chance that it may spill over into Tuesday.
Twelve Open spots are on offer from a field of 112 at Congressional which includes 1995 PGA champion Steve Elkington of Australia, Britons Lee Westwood and Justin Rose and Shigeki Maruyama of Japan.
