Caplan says Clay had offers from teams last year but elected to sit out the season due to concerns regarding the pandemic.
Clay last played for the Cardinals in 2019.
Clay, 32, is a former sixth-round pick of the Dolphins back in 2011. After four years in Miami, the Bills signed him away from the Dolphins and gave him a five-year, $38 million contract that included $20 million guaranteed.
Clay was set to make a base salary of $4.5 million for the 2019 season when the Bills released him. He signed a one-year, $3.25 million deal with the Cardinals.
In 2019, Clay appeared in 15 games for the Cardinals and caught 18 passes for 237 yards receiving and one touchdown.