"Frasier" vs. "Roseanne" at 9 p.m. Tuesdays? It's prime-time's most hotly contested fall matchup -- but it might not happen. ABC appears ready to blink, by switching "Roseanne" out of its current 9 p.m. Tuesday slot and into the 9 p.m. Wednesday slot currently occupied by "Home Improvement," Advertising Age reports this week.

The switch has been rumored ever since NBC challenged the six-year-old megahit "Roseanne" last spring by moving "Frasier," the Kelsey Grammer hit comedy, from Thursday nights to Tuesdays.

"It's an option," ABC spokeswoman Janice Gretemeyer said Tuesday, when asked about the Advertising Age report, "and it still could happen." She said Ted Harbert, ABC entertainment president, "wants to keep his options open." James Anderson, a spokesman for Carsey-Werner Co., which produces "Roseanne," said, "We haven't heard anything -- it's still back and forth." If the switch happens, "Home Improvement," last season's No. 1-rated TV show, would replace "Roseanne" against "Frasier."

All summer, ABC has expressed confidence in the ratings resilience of "Roseanne," which has ranked in the top five throughout its six seasons. But the concern is that "Frasier," even if it didn't beat "Roseanne" every week, might kill its profitability, especially as "Roseanne," with costs bloated by its namesake star's salary to $2 million to $3 million per episode, is among TV's most expensive shows. Meanwhile, "Frasier" summer reruns have only amplified that show's ratings as the new season approaches. "Frasier" has been the top-rated new show for the past seven weeks in a row.