Zach Randolph put in a go-ahead layup with 26 seconds left in OT and the Grizzlies scored the game's final six points to send the series to Memphis even at a game apiece.
A wild finish saw Memphis survive a miraculous four-point play from Kevin Durant in the final minute of regulation and Kendrick Perkins' overtime- forcing putback attempt at the buzzer.
Randolph scored 25 points, Mike Conley donated 19 points with 12 assists and Marc Gasol and Courtney Lee each chipped in with 16 points for the victors.
Durant finished with 36 points and 11 rebounds while Russell Westbrook added 29 points, eight assists and seven boards. The duo combined to shoot just 23- of-56 from the field and the Thunder connected on only 39.8 percent of their shots to lose homecourt advantage in the series.
The Memphis Grizzlies took everything the Oklahoma City Thunder had on Monday and stole Game 2 of their Western Conference quarterfinal series with a thrilling 111-105 overtime victory.