Diamondbacks designate Roberts for assignment

The Arizona Diamondbacks have designated infielder Ryan Roberts for assignment and reinstated infielder John McDonald from the 15-day disabled list.

Roberts hit .252 with nine doubles, six home runs and 33 RBI in 82 games with Arizona this season.

He appeared in 372 games over four seasons with the Diamondbacks and hit .254 with 34 homers and 133 RBI.

McDonald was placed on the disabled list on July 2 with a strained left oblique. He is batting .267 with four homers and 12 RBI in 33 games with Arizona this year.