Quentin entered Tuesday's game with four home runs and a team-best 20 RBIs in July.
He felt some discomfort in his knee late in Sunday's victory over the D-backs in Phoenix and then didn't appear in Monday's victory over the Reds.
Since Quentin won't play in Wednesday's series finale, he'll get two full days of rest with Thursday's off-day before the team opens a three-game series Friday against the Yankees at home.
"The knee was tweaked in Arizona, he didn't play Monday and took another swing today that lit it up," Black said. "Hopefully, he'll be back in the lineup on Friday."
It was last October, right after the end of the regular season, when Quentin had arthroscopic surgery on his right knee. His participation in Spring Training was slowed after the surgery, and he appeared in only four games and had 14 at-bats.
After a slow start -- Quentin hit .239 in April and .191 in May -- he adjusted his stance, standing more upright in order to take stress off his knees. He then hit .366 in June before continuing his productivity this month.
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. Jamal Collier is an associate for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.