I am not at the NFL combine in Indianapolis, but I was able to listen to Harbaugh's press briefing on the podium and then in a more informal setting afterward. Here are some nuggets:Harbaugh said defensive lineman Tank Carradine recently had a knee surgery to clean up a mass on his knee. He missed all of last season as he recovered from a 2012 torn ACL. The second-round pick is expected to contribute this season."He wasn't able to straighten out his leg before that and then they took that [mass] out and his leg went straight," Harbaugh said.