Baltimore Ravens rookie linebacker Sergio Kindle, who fractured his skull in a fall down a flight of stairs in July, is "ahead of schedule" and hasn't been ruled out for the 2010 season, coach John Harbaugh said Tuesday.

"Based on what I've been told -- and some of this comes from Sergio, who is very optimistic -- but also from the doctors who say he's ahead of schedule," Harbaugh told reporters Tuesday. "He's really recovering very quickly, which is really encouraging. That's why we want to make sure we get him here and have all the doctors compare notes with the people down in Dallas and see exactly where he's at."

The Ravens still haven't signed Kindle, who is scheduled to travel to Baltimore by the end of next week to see a neurologist. Because he is unsigned, Kindle is not permitted to visit the team at its headquarters when he travels to Baltimore.

Kindle, drafted in the second round by Baltimore, will be placed on the physically unable to perform list to start the season, meaning he'll miss at least the Ravens' first six games.

Harbaugh said the Ravens would consider playing Kindle later in the season if he shows he is recovered from his injury.

"I think we have to evaluate it from there and see where we're at," Harbaugh told reporters.