INDIANAPOLIS — Martin Mayhew, the Lions general manager, said today that the Lions will be aggressive but selective when free agency opens on March 5.

“I think there are always quality guys out there at every position. I think we’re going to be aggressive in free agency, but be more selective,’’ Mayhew said today.

The unrestricted free agent pool will be smaller than usual this year because the 2010 season will be uncapped because a new collective bargaining agreement has not been reached. As part of the deal, players must have six years of NFL experience to be unrestricted, instead of the normal four years.

“I think things are going to happen fast this year. With a smaller group of players I think things are going to happen pretty fast,’’ Mayhew said.

Of course he, would not be specific. He wouldn’t name players or position groups that would be a priority.

The Lions do need a veteran quarterback as a backup to Matthew Stafford, but Mayhew said that is not something that necessarily needs to be addressed early in free agency.