Westbrook had 40 points, 13 rebounds and 11 assists as his golden February continued, yet the Thunder were beaten at Moda Center.
LaMarcus Aldridge finished with a double-double of 29 points and 16 rebounds, while Damian Lillard also had 29 points.
In the end, a missed free-throw by Westbrook in the dying stages proved costly.
He was inexplicably fouled by Wesley Matthews while shooting a desperate three with 2.5 seconds remaining.
Westbrook missed his first free-throw and the Thunder's hopes were dashed, having being outscored 37-23 in the fourth quarter.
The Golden State Warriors bounced back from their loss to the Cleveland Cavaliers with a 113-89 thrashing of the Toronto Raptors.
Klay Thompson (25 points) and Steph Curry (22) combined to see the Warriors to a resounding victory.
LeBron James (sore back) sat out as the Cavs suffered a 93-86 loss to the Indiana Pacers at Bankers Life Fieldhouse.
The Boston Celtics came from 16 points down to get past the Charlotte Hornets 106-98 at TD Garden.
It took double overtime, but the New York Knicks claimed a rare win by overcoming the Detroit Pistons 121-115.
The Chicago Bulls enjoyed a 96-89 win over the Minnesota Timberwolves and the Houston Rockets battled past the Brooklyn Nets 102-98.
The fast-finishing Los Angeles Clippers claimed a 97-79 win at the Memphis Grizzlies and the New Orleans Pelicans edged the Miami Heat 104-102.
The Utah Jazz cruised past the Denver Nuggets 104-82, the San Antonio Spurs beat the Sacramento Kings 107-96 and the Los Angeles Lakers were 101-93 victors against the Milwaukee Bucks.
The Philadelphia 76ers edged the Washington Wizards 89-81 and the Atlanta Hawks were too good for the Orlando Magic in a 95-88 victory.