NEW YORK (AP) — Jake Lamb was reinstated from the disabled list Friday by the Arizona Diamondbacks, who hope the return of their All-Star third baseman will boost a struggling lineup.The move came just a few days after the NL West leaders lost center fielder A.J. Pollock for the next four to eight weeks because of a broken left thumb. Pollock was hitting .293 with 11 home runs and 33 RBIs, pacing the team in all three categories.Arizona began the day with a .220 batting average that ranked last in the majors. The Diamondbacks had lost seven of eight heading into a nine-game road trip.Lamb was set to bat third Friday night against the New York Mets, between Steven Souza Jr. and slumping slugger Paul Goldschmidt. The 27-year-old had been sidelined since April 3 with a sprained AC joint in his left shoulder. He was 5 for 18 (.278) with five RBIs in the first four games of the season after hitting .248 with 30 homers, 105 RBIs and an .844 OPS last year.In three rehab games at Class A Visalia, Lamb went 2 for 11 (.182) with two doubles.To make room on the roster, Arizona optioned infielder Christian Walker to Triple-A Reno. In addition, right-hander Braden Shipley (right elbow inflammation) was activated from the 10-day DL and optioned to Reno.Walker has played in 16 games during two stints with the Diamondbacks this season, going 2 for 16 (.125) with a home run, a double, two RBIs and three walks.In other news, Arizona manager Torey Lovullo said veteran right-hander Clay Buchholz is expected to be called up from Reno to start Sunday against the Mets, giving Zack Greinke extra rest. Greinke would be pushed back a day to pitch Monday in Milwaukee.With some bad weather in the forecast, the Diamondbacks are just hoping Buchholz won't have any trouble traveling across the country and getting to New York in time.___More AP baseball: https://apnews.com/tag/MLBbaseball