It's tough being No. 1. If you're NBC heading into the 1986-87 television season, you've got a position to protect. Will the old shows hold up another year? Will any of the new ones hurt you? Will any help?

And it's not easy being No. 2. If you're CBS, the question is, how do you take a run at No. 1 without falling to No. 3?

But it's easy if you're No. 3. You can try what you like. You ain't got nothing to lose. Well, not exactly. Still, it is a crap shoot, as they say in broadcast circles, and if you lose, you can't fall any further than third.

In truth, prospects for the coming season are calculated more closely than that. At ABC, there is guarded optimism. Optimism, in that the network feels it's offering a stronger schedule than last year's. Guarded in that it doesn't expect to overtake CBS, much less NBC, this fall.

"What we'd seen was that we'd established ourselves on four nights -- Sunday, Monday, Tuesday and Wednesday," said Marvin Mord, ABC's vice president for marketing and research services. "We needed to shore up some spots on those nights to assure ourselves of being competitive or a force on those nights."

There are 23 new shows on this fall, with ABC offering nine of them, two more than each of the competitors. Most of ABC's shows, one way or another, stress human relationships. And one of them -- "Sledge Hammer!" -- stresses absurdity, with David Rasche (on the cover) starring as a macho cop who talks to his gun. Yes, talks to his gun. Naturally, that's the ABC show that's drawn the most, and generally favorable, attention. Several of the network's other shows will undergo reworking and some have been moved to new timeslots.

Mord, in a far-ranging interview, offered insights into ABC's strategy for the season and appraisals of his and the other networks' shows. (The accompanying program mini-grids indicate what the networks' prime-time schedules will be when new shows settle into regular timeslots. The programs in bold capital letters are new this fall.) Here, with Mord serving as guide, is a day-by-day look at the season -- by parts analysis, prediction and strategy as seen through the ABC looking glass.

ABC's situation on Sunday night is rather basic: It throws the "Disney Sunday Movie" up against some of the top-rated shows on television ("60 Minutes" and "Murder, She Wrote") and hopes that more people will watch the ABC movie than watch the other nets' movies at 9.

CBS, as usual, will have the best ratings on Sunday. But there are points of optimism for ABC. "The advantage of the Disney movie is that it ... delivers large family audiences," said Mord, while the evening's dominant shows appeal primarily to adults. "The Disney movie was the number three show for kids last year behind 'Cosby' and 'Family Ties,' " said Mord. "It's really going to be a tough road for NBC's shows. It will be hard for 'Our House' to get off the ground against Disney, and I see no hope for comedies ('Easy Street,' 'Valerie') from 8 to 9. They may be the first shows to come off the air."

ABC will also try to diversify its 9 p.m. movie offerings. "We'll have more made-for-TV movies," said Mord. "Those that had been seen already on cable didn't perform all that well."

"MacGyver," who seemed to discover a bit of an audience last season, will discover girls this season. "MacGyver is being given more relationships," said Mord. "He's not just going to solve cases through his strategies." ABC also hopes the show will attract kids, teens and women to balance its mostly-male "Monday Night Football" audience. Its predecessor in the timeslot, "Hardcastle and McCormack," had few kids in its audience, said Mord.

The kid-appeal of "MacGyver" may put it on a collision course with NBC's new "ALF," a comedy revolving around the arrival of a crotchety, Muppety Alien Life Form in the garage of suburbanite Willie Tanner (Max Wright) and his family. If the funny lines of the pilot keep coming out of the word processor, it could be a hit. Mord said he wasn't sure of its ability to grab an audience, but he conceded the next best thing: "I think it will be an enormous merchandising hit."

The Monday summary: "I expect NBC to be third that night. I'm not sure who's going to be first," said Mord, acknowledging CBS' strong comedy lineup.

Mord smiles about Tuesday. That's when "Who's the Boss?" and "Moonlighting" are on. "They're peaking," he said, "and maybe this year we'll have 22 episodes of 'Moonlighting' [so that no episode will have to be repeated more than once in the spring]. Our problem is that it's so stylishly crafted. It takes a 10-day shoot rather than the usual seven to do a show.

"There are some shows people make a point to stay home and see. 'Cosby' is one. 'Miami Vice' was one. 'Hill Street' used to be. 'Dynasty,' 'Dallas' and 'Knots Landing' have continuing audiences. We feel we have that kind of audience Tuesday and Wednesday with 'Moonlighting' and 'Dynasty.' And on Monday for men."

And the growing appeal of "Who's the Boss?" and "Growing Pains" won't hurt. "We think 'Growing Pains' developed into a strong show last season," said Mord. "Kirk Cameron is getting 5,000 to 6,000 letters a week. It's similar to what's happened in 'Family Ties' " where Michael J. Fox has emerged as a star.

At 10 ABC introduces "Jack and Mike," with Shelley Hack and Tom Mason playing a Yuppie Chicago couple. "It figures to hold most of 'Moonlighting's' audience," said Mord. "The strength of the show is the relationship between the leads -- not unlike the Cybill Shepherd-Bruce Willis relationship. Theirs is more of a lifestyle conflict within a loving relationship. We feel it can develop into a significant hit by next season. That's why it's scheduled behind 'Moonlighting.' It's a good time period with a strong lead-in ...

"We're feeling comfortable about Tuesday night."

The ABC idea for Wednesday is to establish a pair of comedies in the first hour of prime time and go with "Dynasty" and a remodeled "Hotel" in the last two.

" 'Perfect Strangers' did well last year," said Mord, "and from what I hear the relationship is even stronger this year" between Mediterranean immigrant Bronson Pinchot and Chicago cousin Mark Linn-Baker.

It's backed up by newcomer "Head of the Class," opposite NBC's "Highway to Heaven" and CBS newcomers "Together We Stand" and "Better Days."

" 'Head of the Class' is our strongest comedy pilot," said Mord. "It's a class of vulnerable, bright, fragile students led by Howard Hesseman. He's even stronger than he was as Johnny Fever in 'WKRP in Cincinnati.' He's not Kotter, and it's not 'Room 222.' "

James Brolin is now co-owner of the "Hotel." Efrem Zimbalist Jr. and Michelle Phillips join the cast, and the Brolin-Connie Sellecca romance continutes to heat up.

Mord respects the attraction of "Highway" but feels "Magnum, P.I." and "The Equalizer" have already posted their best Nielsens. "CBS will be third in every time period," he said. "NBC will be second, except possibly at 8 with 'Highway to Heaven.' "

"Thursday will be a very competitive night for us and CBS," said Mord. "It's unlikely ABC would move out of third, but we expect to maintain a position bether than before." NBC, of course, owns Thursday.

Mord praised "20/20" for carrying on gamely all these seasons against "Hill Street" and "Knots" with no strong lead-in program. Now "Knots" has been moved up an hour, going against "The Colbys." For some viewers, that will be VCR time.

"I think 'Knots' is now stronger than 'Dallas,' CBS' best serial. I think they'll suffer for moving it to 9," said Mord. "They'll also hurt 'The Colbys.' "

At 8, ABC offers a new magazine show, "Our World," with Linda Ellerbee and Ray Gandolf hosting. "It'll get chewed up, sure, by 'Cosby,' but it's not a piece of cake. It will find an audience," said Mord. "It's not a normal magazine show," he said, citing the writing of Ellerbee and Gandolf that he hopes will set it apart. One of their first segments will be a reprise of the year 1969.

Mord noted that even if "Our World" places low on the Nielsen list each week, the cost of producing such a program -- one-half to one-third of a regular series -- makes a smaller audience acceptable. "We can get a lower Nielsen number and still be profitable." And, like "20/20," its spring episodes will be originals while everyone else has reruns.

Friday is the fun night for ABC. "We've made a frontal attack," said Mord. Leading the charge is "Sledge Hammer!" starring Rasche as a tackily dressed cop in a spoof of the Rambo style. Sledge, who talks to his .44 magnum and has appropriately named it Gun, was to be slotted at 9:30. But the show's been mobilized to the front line at 9, opposite "Dallas" and "Miami Vice."

"We moved 'Sledge' to 9 based on a strong half-dozen scripts," said Mord. "When you read a script on a plane and find yourself laughing out loud and people are staring at you, you think there's something in it."

It would be easier to slot "Sledge" in a less demanding time period, said Mord, but the advance word of mouth about the show has been so positive that Mord feels it has a chance to prevail in the timeslot. "We've seen some very funny and sustained comedy," he said.

"Sledge" is followed by another new show, "Sidekicks," a Karate Kid-style program. A good show, said Mord, "but it doesn't have the heat of 'Sledge.' "

At 10, opposite "L.A. Law," another program enjoying advance praise, ABC has "Starman," a TV spinoff of the feature film. CBS offers "Falcon Crest."

"Law" is the work of Steve ("Hill Street") Bochco, and Mord acknowledges that it should be a well-written series. "But I think its audience will be limited," he said. "From what I've seen, the characters are not people who will be likeable."

And in the past, "Falcon Crest" has lost some of the "Dallas" audience, which is heavily female, so, speculated Mord, maybe those who don't stay around after the Ewings' story will tune in to "Starman." And it should appeal to them. "It's not a science-fiction show," he said. "It's a father-son relationship show -- where the father just happens to be an alien."

The show also has Robert Hays going for it, said Mord, along with solid production work.

"It's a crapshoot," said Mord of Friday. "We have nothing to risk -- we can only go up."

On Saturday the "Life With Lucy" show "certainly will get sampled," said Mord. The series re-teams Lucille Ball with Gale Gordon. Ball "clearly demonstrates a tremendous amount of energy," said Mord, even at 75. "Gale Gordon is even older ... If the rest of the family can blend in ... It's '50s television in a way."

"Lucy" is followed by "The Ellen Burstyn Show," in which she is backed by Elaine Stritch and Megan Mullally as members of a multi-generation household.

At that point, there's a glitch in the ABC schedule, with "Heart of the City" at 9. Airing just after "Lucy" and "Ellen Burstyn," the show may have a transition problem. Mord thinks "it would be better suited to 10 p.m. on a weeknight. The show has the same reality-base to it that 'L.A. Law' has." Robert Desiderio plays a widowed detective who has to cope with a pair of teen-age children as well as crooks. "It's my favorite show," said Mord, himself a father of teen-agers. "I think it's on the money. But it may have difficulty getting off the ground."

Four women may hold it down. "'Golden Girls' is clearly the dominant show of the time period," said Mord. "I wouldn't be surprised to see the Burstyn audience go to 'Golden Girls.' "

"Spenser: For Hire" will have a new look at 10. Juanita Bartlett, who left a stamp on "The Rockford Files," is the show's new executive producer. And Robert Urich gets a new love interest. Barbara Stock moves away from Boston, and the show, and Carolyn McCormick moves in as an assistant district attorney. McCormick's job will bring the pair together more than Stock's did.

It's not out of the question, said Mord, that ABC could move to second place on Saturday night.

From Mord's desk, the new season appears to be on an even keel. "In going through our development we were pleased," he said. "I don't recall going through a development season in years when there were no dogs."

On the other hand, he sees no blockbusters on the fall schedule. "It's hard to tell if there's a 'Mork and Mindy' or a 'Cosby' out there. I don't see that on any of the three networks."

The ABC outlook: "We expect to be the only network to make ratings gains," Mord said, "though we expect still to be third in the fourth quarter. But we will close the gap considerably. There's a chance we could pass CBS in the first half of 1987."

But of course, as he said of Friday night, it's a crapshoot.