Selected 245th overall out of Oklahoma, Millard ran for 538 yards and six touchdowns on 98 carries while playing in 48 games with 18 starts for the Sooners.
He also made 70 catches for 677 yards and seven touchdowns. As a senior last season, Millard had 17 carries for 97 yards and a TD and 11 receptions for 78 yards and a touchdown.
The 49ers will hold their rookie minicamp this weekend.
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