No, Asimof isn't a Paper Lion in training, nor is he as snappy a writer as Plimpton but there isn't much he doesn't know or like about the New York Giants, and he sat it out play-by-play with them for two years. The Seven Days to Sunday he records is the crisis week in 1967 before the game which could make or break the season. The Giants had suffered a sloppy defeat, ignominously dumping them into third place the day before, from the Chicago Bears; they faced the Pittsburgh Steelers and four more tough games in a have-to-win situation. And the Giants' morale had been cut down to pygmy size. This follows the emotional and tactical arrangements by coach Allic Sherman as he tried to get his fumbling football players together again. In the huddle you'll get close-ups of each player -- Fran Tarkenton, whose ""squareness is so boyish it is actually refreshing,"" the unpredictable genius of Homer Jones, notorious for confounding his own quarterback, the enthusiasm of Ken Avery ""All pride and a yard wide."" the jazzy outlook of Spider Lockhart, the insecurity of young Freeman White, and the courage of Tucker Frederickson (who was to be permanently injured in next Sunday's game.) A locker-room log that is another intimate, exciting look at our newest national past-time.