Cook, who missed most of his rookie season in 2017 after suffering a torn ACL, rushed for only 38 yards on 10 carries in last week's 29-29 tie with Green Bay.
Cook suffered his knee injury in Week 4 a year ago. He was brought along slowly in the preseason and appeared in only one game, rushing for one yard on two carries.
A second-round draft pick out of Florida State in the 2017 NFL Draft, Cook burst onto the scene by rushing for 127 yards on 22 carries in his professional debut.
Cook amassed 354 yards rushing on 74 attempts, averaging a robust 4.8 yards per carry, before suffering the torn ACL in Week 4 against the Detroit Lions last season.
Murray, a former 1,000-yard rusher for Oakland, proved to be a solid replacement for Cook, finishing with 842 yards and eight touchdowns on 216 carries as Minnesota advanced to the NFC Championship Game.