Ravens seek permission to interview four NFL assistants

The Baltimore Ravens have begun identifying potential candidates to succeed deposed head coach Brian Billick. And at least in the early stages of their search, the emphasis is on the offensive side of the ball.

Baltimore has requested permission to speak with four assistants about its vacancy -- assistant head coaches Jim Caldwell of Indianapolis and Tony Sparano of Dallas , and offensive coordinators Josh McDaniels of New England and the Cowboys' Jason Garrett.

All four men are involved with offenses which statistically ranked among the top five in the league in 2007. And all are with franchises that have reached the playoffs but have first-round byes this week.

By league rule, teams seeking new head coaches can interview assistants from clubs with playoff byes this week, but the sessions must take place by Saturday. After that, coaches from playoff franchises can only be interviewed after their teams are eliminated or in the "open" week between the conference championship games and the Super Bowl.

It has not yet been determined when the interviews with the four assistants will take place.

Billick was fired on Monday after nine seasons, during which he compiled a record of 85-67, counting the playoffs. He delivered a Super Bowl XXXV championship in 2000, but his offenses struggled annually, and he failed to ever develop a young quarterback. Improving in both areas could be a priority in the search for a new coach.

In his nine seasons in Baltimore, the Billick offense never statistically ranked higher than 14th in the league. In six of those years, it was 20th or lower, including a No. 22 finish in 2007. Given such a track record, the emphasis on offense in the early interview stages is not surprising.

That said, some veteran players are lobbying hard for Ravens defensive coordinator Rex Ryan to replace Billick. Even though Ryan was technically dismissed with the rest of Billick's staff on Monday, owner Steve Bisciotti and general manager Ozzie Newsome have indicated he will be interviewed for the head coach position.

McDaniels is only 31 years old and completed just his second season as a coordinator, but presided over a Patriots' offense that ranked No. 1 in the league and set new records for points and touchdowns scored. Garrett is in his first season as a coordinator, and the Dallas offense ranked third in the league. He will interview with Atlanta Falcons officials on Friday for their opening.

Sparano will also interview Friday with Atlanta owner Arthur Blank. He worked primarily with the offensive line this season, but called the plays for then-Dallas coach Bill Parcells in 2006. He is expected to be a candidate in Miami if Parcells decides not to retain current coach Cam Cameron. Caldwell has been the assistant head coach to Tony Dungy in Indianapolis since 2002 and is a former Wake Forest head coach.

Sources said that Ravens management has an extensive working list of candidates which includes more than one current college head coach.

Senior writer Len Pasquarelli covers the NFL for ESPN.com.