A source said that forward Doug McDermott signed a $32 million, three-year contract with the Spurs. This was in addition to an earlier roster upgrade for San Antonio, once free agency had opened.Agent Mark Bartelstein revealed to Adrian Wojnarowski that the Spurs added power forward/center Zach Collins in a three-year deal worth $22 million.McDermott signed a $22 million contract with the Indiana Pacers in 2018 as one of the first players who agreed to a contract. McDermott, a 29-year-old veteran, set several career records for the Pacers this season. These included points (13.6), rebound (3.3), assists (1.3), field goals percentage (53.2), minutes per games (24.5), and starts (29).McDermott was an elite 3-point shooter, and he started his career at Creighton as a star player. He played for his father's team. McDermott played a crucial role on a Pacers team that had to deal with a series injuries to its wing players, Caris LeVert and T.J. Warren, throughout the season.Collins was not offered a qualifying offer by the Portland Trail Blazers, so Collins became an unrestricted free-agent. Collins was the 10th overall selection in the 2017 draft. Collins was once part of Portland's core but injuries have limited his career to just 11 games in the past two years.Collins, 23, has made a comeback after three operations on his left ankle in the last year.Collins initially injured his ankle in an NBA restart in Walt Disney World. He had to have surgery in September 2020 to fix the broken bone. Two setbacks caused him to be sidelined for the 2020-21 season. He had to have surgery in December and June to fix left medial malleus stress injuries.Collins missed four months of the 2019-20 season due to a left shoulder injury.Collins' career averages are 5.7 points per game and 4.0 rebounds per match, mostly as a reserve. Portland had planned for Collins to move into a starting position -- his 11 appearances in 2019-20 are all starts -- but injuries halted his career.This report was contributed by Tim Bontemps, an ESPN staff writer.