MEMPHIS, Tenn. -- Their 10-point fourth-quarter lead squandered, Marc Gasol had a feeling the Grizzlies would regroup.
And they did.
Gasol finished with 20, and his two free throws with 9.5 seconds extended the Memphis lead to 115-111, assuring the Grizzlies of their fourth straight home win.
"We have faith in each other," Gasol said. "We know everybody can make plays. We did kind of run a little out of gas. But we won. In the end, that's all that matters."
Randolph made two free throws with 0.3 seconds left in regulation, sending the game to overtime tied at 102.
"That one stung," Wizards guard Randy Foye (11 points) said of the play leading to the foul. "We had no time on the clock and up by two. We stopped the initial play, and Zach Randolph went to the basket and got fouled. This one is going to be hard to swallow."
Mike Conley scored 22 for Memphis. Randolph had 19 rebounds, and Gasol added 11 boards as the Grizzlies outrebounded the Wizards 54-41 and outscored them in the paint 62-42. Memphis is now 6-0 at home this season against teams with losing records.
"We've got to win the games we're supposed to win, if we want to get to where we want to get to," Mayo said. "The Wizards are capable of beating any team in the NBA."
Gilbert Arenas led the Wizards with 30 points, connecting on 12-of-26 shots from the field, including 5-of-11 from 3-point range.
"We just couldn't get a break," Arenas said. "We are just not getting the breaks that we need. They are all going against us."
Memphis went up 111-106 in the extra period on Randolph's tip with 1:49 left.
Washington closed to 113-111 when Arenas made 1-of-2 free throws with 32.4 seconds left. But Gasol's two free throws gave Memphis enough of a cushion for the victory.
"We couldn't make a big stop," Wizards coach Flip Saunders said. "We couldn't get a key rebound. I can't fault our guys. We were down 10 and came back."
The Wizards, who trailed by 10 in the fourth, tied the score at 100 when Brendan Haywood hit one free throw with 30.8 seconds left in regulation.
Two free throws by Butler with 9.4 seconds left completed a 7-0 run by the Wizards after Memphis had taken a 100-95 lead with just over 2 minutes left.
After Randolph tied it, Arenas fired a desperation shot from the right corner, but it spun out as time expired in regulation.
"We just kept making enough plays to get the win," Memphis coach Lionel Hollins said. "It was a tough battle. It looked like it was won, then it looked like it was lost a few times. We just hung in there and kept playing. That's what you have to do in those situations -- play until it is over."
"We needed everybody to step up and play," Hollins said, later adding: "Everyone did what they needed to do to get a win."
Trailing 51-50, Memphis opened the second half with a 17-7 run.
But neither team could take hold of a lead. Washington chipped into the lead at times behind Jamison's 10 points in the third quarter.
Andray Blatche's 3-pointer from the right corner cut the Memphis lead to 81-80 entering the fourth.
Memphis got the game's first double-digit lead by opening the fourth with an 11-2 rally for a 92-82 lead on Mayo's 20-footer. Washington started the quarter 2-of-10 from the field, and committed four turnovers, helping Memphis extend the lead.
Meanwhile, Memphis has won 13 of its last 20 after starting the season 1-8.
"All we've been doing is great," Gasol said, "and we see the results. Now, we have to work harder because everybody is going to make adjustments because everybody knows we're playing good."
The Wizards are one of only four teams that the Grizzlies have a winning record against. The Raptors, Clippers and the Bobcats are the other three. The Grizzlies have won five straight home games over the Wizards. The last time Washington won in Memphis came on Nov. 3, 2004. Arenas had committed seven turnovers in three straight games entering Monday night. He had four miscues against the Grizzlies. Washington's 11 3-pointers was a season high for shots made beyond the arc. Memphis had 15 offensive rebounds, and have grabbed at least 10 offensive rebounds in 11 straight. Memphis leads the league in offensive rebounds.