ABC Goes on the Sitcom Defensive : Television: The network puts top-rated ‘Home Improvement’ in ‘Roseanne’s’ time slot to counter NBC’s plan to move ‘Frasier’ to Tuesday night.

Fans of America’s most popular TV program, “Home Improvement,” and a trio of other successful ABC sitcoms, including “Roseanne,” may be scratching their heads when they look for their favorite shows next month. They won’t be where they used to be.

ABC announced Tuesday that “Home Improvement” will swap time slots with “Roseanne.” Beginning with the season premiere on Sept. 20, “Home Improvement” will air Tuesdays at 9 p.m., where “Roseanne” has been a bastion for five seasons. The season premiere of “Roseanne,” meanwhile, will be bumped to the next night at 9, in “Home Improvement’s” old Wednesday time slot.

“Grace Under Fire” will continue to follow “Home Improvement” at 9:30 p.m., but now on Tuesdays. “Roseanne” will be followed on Wednesdays by “Ellen,” last spring’s sleeper comedy series starring Ellen DeGeneres, which has been running on Tuesdays.

ABC’s plan was hatched as a defensive move to prevent NBC from building a powerful night of comedy programming around last season’s highest-rated new series, “Frasier.” NBC made the decision last spring to break out “Frasier,” which had a choice time slot last season after “Seinfeld” on Thursdays, to Tuesday at 9 p.m. this fall.

“(NBC Entertainment President) Warren Littlefield has said that he knew ‘Roseanne’ would beat ‘Frasier,’ and we thought so too. But we think ‘Home Improvement’ will make life unbearable for ‘Frasier’ on Tuesday at 9 p.m.,” said Alan Sternfeld, senior vice president of programming for ABC.

“Home Improvement” is considered to be a more formidable competitor than “Roseanne,” which has shown signs of decline in the ratings, because it has not yet reached its full growth potential after only three seasons on the air.

“We don’t want NBC to achieve a comedy block that will ultimately achieve parity with us,” Sternfeld said. “We’re sort of borrowing from the doctrine of (Gen. Norman) Schwarzkopf: If you’re interested in accomplishing something, use overwhelming force.”

NBC, in a terse statement Tuesday, said: “We think that it’s a very interesting move. It certainly shows that ABC has tremendous respect for ‘Frasier,’ as do audiences. We believe that ‘Frasier’ will perform well, wherever it is on our schedule.”

ABC’s decision met with mixed response at “Home Improvement.”

“My concern is this: Obviously we take great pride in having the No. 1 show on television,” said a perturbed Matt Williams, one of the show’s creators and executive producers. “With this move to Tuesday night against ‘Frasier,’ a different night with different competition, it’s highly unlikely that we’re going to be No. 1 again. How much the audience is divided will determine where we fall in the Top 5.”

Series star Tim Allen expressed sympathy for viewers. “Personally, on one level, I used to hate it when shows moved around. And as a TV viewer from way back, I don’t like it when two good shows are on at the same time,” he said.

But on a professional level, Allen noted, “I love the fact that ABC has created a night for us. That’s the best compliment ABC has ever given us.”

Paul Schulman, president of the New York advertising firm, Paul Schulman Co., predicted that if NBC leaves “Frasier” to fight it out with “Home Improvement,” “Frasier” will drop out of the Top 20.