Elliott, 24, was taken with the No. 4 overall pick by the Cowboys back in 2016. He signed four-year rookie contract worth $24,956,342, which included a signing bonus of $16,350,068.
Elliott was set to make a base salary of $3.85 million for the 2019 season and another $9.1 million in 2020 under the fifth-year option of his contract but elected to hold out for a new deal this offseason.
Dallas re-signed him to an NFL record six-year, $90 million extension that included $50 million guaranteed.
In 2018, Elliott appeared in 15 games for the Cowboys and rushed for 1,434 yards on 304 carries (4.7 YPC) to go along with 77 receptions for 567 yards receiving and nine touchdowns.
Morris, 30, is a former sixth-round pick of the Redskins back in 2012. He played four seasons in Washington before signing a two-year, $3.5 million contract with the Cowboys in 2016 that included a $1 million base salary for the 2017 season.
Morris signed a one-year deal for the 2018 season with the 49ers in August of last year after a rash of injuries to the position. Dallas signed him to a one-year, $1.2 million contract back in July.
In 2018, Morris appeared in 11 games for the 49ers and rushed for 428 yards on 111 carries (3.9 YPC) with two touchdowns to go along with eight receptions for 73 yards receiving.