The Carolina Panthers are actively pursuing improvements in their secondary, hosting free-agent safeties Julian Blackmon and Marcus Williams for visits. Blackmon, the former third-round pick of the Indianapolis Colts, has had a solid five-year career, tallying 300 tackles and 10 interceptions. Meanwhile, Williams, a second-round pick from the Saints, brings a wealth of experience with 469 tackles and 20 interceptions over his eight seasons. Carolina, which had only one safety on its roster before free agency, signed Tre'von Moehrig to a lucrative deal and added veteran Nick Scott back to the mix. The Panthers aim to strengthen their defense in a competitive NFC South.