New Orleans Saints Coach Bum Phillips laughed off reports that he had been fired by owner Tom Benson, but said, "If we don't win five out of these next six ball games, then he has got to make a change."

Asked if he would step down, Phillips replied, "Yep, I think you'd have to. Obviously if the year continues like it is, I would be the first one to go to him and say, 'Tom, you've got to make a change.' "

Phillips already has made a change for this week, naming former USFL star Bobby Hebert to get his first NFL start at quarterback Sunday at Green Bay. Hebert signed a $3.5 million contract with the Saints in August. He has been working behind starter Dave Wilson and Richard Todd . . .

The Chicago Bears might be without the services of quarterback Jim McMahon again Sunday at Dallas, where they will seek their 11th straight victory.

McMahon has a bruise in the joint of his throwing shoulder. McMahon did not play Sunday in Chicago's 24-3 victory over Detroit. Backup Steve Fuller scored two touchdowns. . . .

Los Angeles Rams quarterback Dieter Brock, who had surgery to remove a kidney stone last week, has permission to return to practice and could start against the Atlanta Falcons Sunday. "It's pretty much based on what I can tolerate as far as pain," Brock said . . .

Three masked gunmen took at least $300,000 in concession stand revenues at San Diego's Jack Murphy Stadium about five hours after a record crowd of 58,566 watched the San Diego Chargers beat the Los Angeles Raiders, 40-34, in overtime Sunday.

No one was injured when the robbers, armed with a rifle, shotgun and pistol, walked into a basement room where the vault for Service America Corp., the stadium concessionaire, was located. Police Chief William Kolender said that the robbery was the largest in San Diego history.