 Complete the following phrase:  On March 7, 2016, quarterback Peyton Manning retired after 18 NFL seasons during a press conference at the teams Dove Valley headquarters. While he left a legacy behind football wasnt Peyton Mannings only accomplishment. Peyton and Ashley Manning established the PeyBack Foundation in 1999 to promote the future success of disadvantaged youth by assisting programs that provide leadership and growth opportunities for children at risk. Following Mannings retirement, the Broncos have undergone changes at the quarterback position, including the free agent departure of backup quarterback Brock Osweiler to the Houston Texans, the trade acquisition of Mark Sanchez from the Philadelphia Eagles and the selection of Paxton Lynch during the 