"(Russ) saw that we weren't making shots," Durant said.
In addition, Perkins suddenly was one technical away from earning a one-game suspension when he was whistled for his 12th technical of the season with 4:44 left in the quarter.
After that dismal opening period, OKC shot 42.9 percent in the second quarter, 61.9 percent in the third quarter and 58.6 percent in the fourth quarter to finish at 46.2 percent, snapping a run of four straight games of 50-percent shooting or better.
Defense also spurred the Thunder's comeback. The Lakers were outscored 58-44 after intermission, shot 36.8 percent in the second half and had managed just 21 points in the first 17 minutes after halftime.
By that time, the sellout crowd of 18,977 had started booing the home team.
After being outrebounded 18-10 in the first quarter, the Thunder beat the Lakers 38-27 on the boards and finished with 19 offensive rebounds, which led to 23 second-chance points.
"We did a great job the second half defending," Westbrook said.
OKC also burned LA in transition, outscoring the Lakers 25-8 in fast-break points.
"Oklahoma City didn't do anything tricky," LA coach Mike Brown said. "All they did was come at us in transition and play pick-and-roll. Those two things were it."