The Reds will be without rookie sensation Cody Lamb for an extended period of time after the infielder suffered a Grade II hamstring injury over the weekend.

Lamb, 21, was injured in the eighth inning of Saturday’s game against the Milwaukee Brewers while running to first base. He was diagnosed with the hamstring strain on Sunday and is expected to miss six to eight weeks.

This is a tough break for Lamb, who was hitting .269 with six home runs and 16 RBI in 37 games this season. He had been playing mostly second base and shortstop but also saw …