03/29/2012 08:27 am ET Updated Mar 29, 2012

Katie Couric Will Co-Host 'Good Morning America' For A Week

As its ratings battle with "Today" reaches a fever pitch, "Good Morning America" is deploying a former morning show queen who will really irk its rival: Katie Couric.

The former "Today" star will be co-hosting the ABC morning program — the main enemy of her old show —for a week starting Monday. She will be filling in for Robin Roberts, who is going on vacation. The "GMA" crew made the announcement on Thursday.

"Katie Couric is gonna be sitting in this chair next to George Stephanopoulos!" Roberts said.

"You get to throw away your alarm clock for the week and she has to dust hers off," Stephanopoulos joked.

It will be Couric's first time hosting a morning show since leaving "Today." She arrived at ABC News in 2011 after five years at CBS News, and is set to debut her talk show "Katie" in the fall.

Couric's one-week gig comes as “Good Morning America” closes the gap with “Today,” which has long dominated mornings. In December 2011, "Today" celebrated its 16th year as the number one morning show every week since 1995.

However, its grip has weakened in recent months. ABC News has been gaining on the program, narrowing the gap to the smallest it has been in five years — and even coming in first on two mornings — last week. Couric's appearance may help put "GMA" over the edge.

The shift has reportedly given Matt Lauer even more leverage at "Today," while casting questions about Ann Curry's role at the program. After months of rumors that Lauer would leave when his contract expires at the end of the year, he is reportedly set to sign a blockbuster $25 million-a-year deal to stay on.



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