Detroit coach Lawrence Frank said before the game, that it was mandatory that his team take care of the basketball.
"You just can't give this team extra possessions," Frank said. "Memphis obviously is a very, very good team. But how many of (the turnovers) were forced, and how many were unforced?"
Memphis started 5 of 21 from the field, but eventually got untracked building the lead to double digits.
The Pistons had a 12-4 run opening the third to pull back even.
But Conley converted a 3-point play, and connected from outside the arc to help Memphis carry a 76-66 lead into the final period.
Memphis maintained at least an eight-point advantage through the fourth quarter, although both teams struggled down the stretch. The two teams were a combined 9 of 35 in the final period, and Memphis outscored Detroit 14-12.
"Nobody could make a shot in the fourth quarter," Memphis coach Lionel Hollins said. "I'm happy we were ahead and our defense was still strong."
The Grizzlies head to San Antonio on Saturday to face the Spurs, who are well-rested even though it cost the team $250,000 for sending Tim Duncan, Tony Parker, Manu Ginobili and Danny Green home before the finale of a six-game road trip in Miami on Thursday night.
NOTES: The Grizzlies have won six straight in the series. ... Randolph entered the game with 12 double-doubles in Memphis' first 13 games. He finished with eight points and five rebounds. ... The Pistons 22 turnovers matched a season high for a Memphis opponent.