Gasol scored a career-high 39 points and the Grizzlies shot 70.9 percent from the field in the second half and 58.8 percent overall in their 108-98 victory over the Wizards on Monday night.
"We came out in the second and played hard," said Gasol, who also had 10 rebounds and bettered his previous career high of 37 points. "We want to be in that playoff race and this game was crucial."
Arenas led Washington with 37 points -- his 27th 30-point game of the season -- and Antawn Jamison had 35. The Wizards had won three straight.
"It was a hard game and they were great," Arenas said. "You can't take that away from them."
Washington led until late in the third quarter but was done in by the Grizzlies' shooting in the second half. The Wizards shot 38 percent in the final two periods and 46 percent overall.
"The second half of the game, they really got the juice. We lost our focus," Washington coach Eddie Jordan said. "They came out and went to Gasol and we just couldn't stop him."
The Wizards entered the game ranked eighth in scoring, averaging 100.2 points.
"Offensively, I don't know what we were doing. They did a good job of staying poised," Jamison said. "We thought we had a comfortable lead and kept it going back and forth, back and forth. But that is no excuse."
"We got a much needed win tonight after a tough stretch of games over the last week," Memphis coach Mike Fratello said. "We came out with a lot of energy in the second half."
The Grizzlies took their first lead, 68-67, with just over 3 minutes left in the third quarter. Jones capped a 13-3 run with six straight points, on three free throws and a 3-pointer.
Memphis ended the period with five points from Jones, on a 3-pointer and a layup, for a five-point advantage at 79-74.
Jones had 12 points in the quarter.
The Wizards had a 10-point run midway through the fourth period, taking the lead at 84-82 on Arenas' 3-pointer.
Arenas drove hard to the basket to end the first half and give the Wizards a 52-41 advantage at intermission.
Washington built a 14-point lead, 48-34, late in the second period behind a 15-7 run.
Jamison had 21 points in the first half, two more than his season average.
Gasol kept the Grizzlies in the game with 19 first-half points.
Gasol fell two short of the Grizzlies' scoring record of 41
set by Bryant Reeves in 1998. ... F Caron Butler, who joined the
Wizards' starting lineup in December, left in the third quarter
with stomach flu. He failed to score in 25 minutes. ... Jamison's
six 3-pointers were a career high and his total points were a
season high. ... The Wizards made 10 3-pointers.