If the NFL players strike, each television network hopes to replace its most popular, pricey sport with one of three less glamorous alternatives: college football, Canadian football or movies.

If there's a strike, ABC says, the network would replace its prime-time Monday (and Thursday) night games with entertainment programming -- primarily movies, and some specials. CBS Sports reports several alternatives under discussion, including a series of college games yet to be negotiated with the NCAA. NBC Sports would go ahead with an agreement made earlier this year to telecast Canadian Football League games in the event of a strike.

This fall marks the start of a five-year, $2 billion television contract between the NFL and the networks. Some say that contract only served to hurry a demonstration of official angst from players who've watched pro football TV and cable deals blossom in recent years, while their salaries have risen at a comparative snail's pace.

Officials at two of the three networks say the loss of NFL games -- for part or all of the season -- would not seriously hurt profits, since no games also means no rights payments. (The payments would approximately double this year over last year.)

"No one is suggesting these (alternatives) would get comparative viewer levels," said Neal Pilson, CBS Sports president, whose alternatives included the college games and expanded "Sports Sunday" anthology coverage of such sports as boxing and racing, and NBA and NHL games later in the season if a strike persisted. "But the fact is we would not be paying the NFL the very high rights fees. We think it's quite possible we would maintain our profit margins."

"Either they play or they don't," said Roone Arledge, ABC News and Sports president, yesterday. "And unlike the other networks which have to scramble around and find other sports to fill in, we don't think putting Canadian football on in prime time is an option for us.

"We'll go with entertainment," he said.

"We expected . . . well, Monday Night Football is not as profitable in the first year of the contract as in other years, and it's not as profitable as it used to be, because the rights are so high," said Arledge. "It (a strike) will hurt us, but I don't think the profits are as important to us as the programming. To put in all this new programming will, I'm sure, hurt the entertainment people more."

The only other pro football on television this fall, if a strike or lockout occurs, might be found on Ted Turner's WTBS-TV-17 superstation in Atlanta.

The NFL Players Association wants to form six 45-man all-star teams to play Sunday or Monday night. Under an agreement with the NFL Players Association, viewers would see the games on Turner's superstation -- if they're lucky enough to be among the 21 million TV set owners (of an 81.5 million total) who can get WTBS. And Turner Broadcasting must be lucky enough to survive an almost-certain suit by NFL owners who think players are bound to them, strike or not, by existing personal-service contracts.

"We don't think the Turner situation is very viable," said Pilson, who had two reasons. The first was the unresolved issue of player personal-service contracts. "Secondly, I don't think the games, if they are played, would be very attractive, because the players are very valuable to themselves, and frankly I think what you'd get is a very loosely played, light-hitting, virtually noncontact sport -- because the risk of injury would be on the minds of every player."

NBC would carry CFL doubleheaders, according to NBC coordinating football producer Ted Nathanson, almost every Sunday through the first week of November, when the regular season ends.

"I think people will watch it just . . . for the hell of it," said Nathanson. " . . . Maybe people will like it. It's a more wide-open game, more passing, there's only three downs. But it's true, people don't identify with the players."