Jamison shot 18-of-22 from the floor for the Wizards, who lost their second in a row after a six-game winning streak. The Grizzlies won for the first time in three games.
Mike Miller and Kyle Lowry each had 17 points for Memphis with 15 of Lowry's points coming in the second half. Caron Butler had 27 points and seven rebounds for the Wizards.
Memphis held the biggest lead of the night for either team, 14 points at 101-87 with 6:10 to play. The Wizards got within 122-118 when Jamison scored inside with 13 seconds left, but could get no closer.
Lowry kept the Grizzlies in front with eight points in the final 2 minutes, including six straight free throws. He finished the night 13-of-14 from the line.