Bobby Petrino resigned as Atlanta Falcons coach yesterday, having lasted only 13 games, and last night was announced as the football coach at the University of Arkansas.

Petrino succeeds Houston Nutt, who stepped down at Arkansas 2 weeks ago and became the head coach at Mississippi.

"The timing of it probably the think that made it most difficult," he said. "Coming to Arkansas was the easy part."

In January, Petrino left as coach at Louisville to take over in Atlanta, agreeing to a 5-year, $24 million contract handed out by a team that felt he could help Michael Vick reach his full potential.

However, the star quarterback came under investigation for a grisly dogfighting operation that led him to plead guilty to federal charges. On Monday, Vick was sentenced Monday to 23 months in prison without ever taking a snap for Petrino.

On Monday night, the Falcons lost to New Orleans, 34-14, and fell to 3-10.

Petrino's stint was one of the shortest for a non-interim coach since the 1970 NFL-AFL merger. Pete McCulley was fired after starting out 1-8 with San Francisco in 1978, and Sid Gillman lasted only 10 games in his second stint as San Diego coach, going 4-6 in 1971 before quitting.

Atlanta owner Arthur Blank and general manager Rich McKay were scheduled to hold a news conference today.

Noteworthy

* Mike Ditka will dissolve his Hall of Fame Assistance Trust Fund in the wake of a report that the charity had given only a small amount of money to needy former NFL players.

* Rams owner Georgia Frontiere, 80, has been hospitalized in Los Angeles with an undisclosed illness, a family spokesman said.

* Packers linebacker Nick Barnett pleaded not guilty to two charges of disorderly conduct stemming from a confrontation outside a nightclub.

* Steelers defensive end Aaron Smith is out for the rest of the season after he tore a biceps muscle during the loss to the Patriots.

* Tampa Bay tight end Jerramy Stevens was suspended without pay for one game for violating the NFL's substance-abuse policy. *