Kelly was fired by the Philadelphia Eagles late in the season after going 6–9 and being eliminated from the playoffs. Kelly went 26–21 in four seasons with the Eagles.
Shanahan hasn't coached in the NFL since being fired by the Washington Redskins following the 2013 season. He has seen success in his 20 years as an NFL head coach, posting a 170–138 record. He won Super Bowls with the Denver Broncos in 1997 and 1998.
San Francisco fired coach Jim Tomsula after just one season. The 49ers finished 5–11 in their first season in the post-Jim Harbaugh era.