51.   But does the estate tax, as owners and league officials maintain, seriously threaten the continuity of the NFL, which in turn would hurt the sport?

52.   But in truth, say players, agents and league officials, the nastiness of the contract battle was not all that surprising.

53.   But league officials must confer today with representatives from ABC before announcing a starting time.

54.   But league officials say that since Chmura was not convicted of a crime, a suspension might not be warranted.

55.   But league officials, who have been in regular contact with the Celtics, disputed that premise Tuesday.

56.   But league officials have said that the date was not soon enough.

57.   But league officials discovered trying to host the World Cup and organize a league at the same time was like trying to balance two beach balls on one nose.

58.   But monitoring objectionable Web sites and speaking out against their content are the easy part, league officials acknowledged.

59.   But one league official doubted that the union could stage exhibition games at all.

60.   But one league official, on condition of anonymity, said an announcement could be forthcoming in the next few days.