The National Football League granted an exception yesterday to its policy forbidding the delayed broadcasts of national network games and clearing the way for WJLA-TV-7 to carry a taped replay, which began at 12:55 Saturday morning, of last night's Redskins' preseason game against Miami, an easy 38-7 victory for the Dolphins.

But the NFL refused to waive its 72-hour advance sellout rule and permit the Redskins to televise the game live, as the Redskins had requested.

The game, televised nationally by ABC, was blacked out locally when more than 1,000 tickets remained unsold at 8 p.m. Tuesday.

Team owner Jack Kent Cooke refused to comment. But a statement from the Redskins stated: "We regret our inability to telecast live the Redskins-Dolphins game. We had no alternative. We are committed to observe the National Football League regulations which are clearcut and unambigious."

Val Pinchbeck, NFL director of broadcasting, said the NFL granted the exception for the tape delay because "of a rather unique set of circumstances--rematch of the Super Bowl teams, the game (subsequently) sold out, and a variety of inquiries from various people." They included many calls to the NFL offices in New York, according to Jim Heffernan, the league's director of public relations.

In Washington, John Long, sales manager of WJLA, the local ABC affiliate, said the station's receptionist received more than 500 calls of complaint yesterday, in addition to other calls being placed directly to the public affairs, sports and programming departments.

Sometime between 2 and 3 p.m. yesterday, after consulting with Commissioner Pete Rozelle, who was in California making arrangements for the funeral of his father, who died Thursday, the NFL agreed to allow the delayed broadcast and granted ABC rights to do so.