Welker, who is entering his 12th season in the league, played with the Dolphins from 2004 to 2006 before being traded to Patriots in 2007 for second- and seventh-round draft picks. He played the last two years with the Denver Broncos
In five of his six seasons in New England, Welker had more than 100 receptions and 1,000 yards receiving.
Last season was Welker's worst statistically since his 2005 campaign with Miami. In 14 games in 2014 with the Broncos, he had 49 receptions for 464 yards and two touchdowns.
In his 11 years in the league, Welker has recorded 890 receptions for 9,822 yards and 50 touchdowns.
Wide receivers Greg Jennings and Michael Crabtree have also visited Miami this off-season. The Dolphins, who finished 8-8 in 2014, lost wide receiver Mike Wallace in a trade last month with the Vikings.
- Erick Fernandez