A confident Minnesota looked in the mood for an upset against the top seeds after leading for most of the first two quarters to take a 48-44 lead into half time.

Timberwolves power forward Julius Randle poured in 20 first-half points to rock the Thunder, who struggled to find their shooting touch in front of an expectant home crowd.

Oklahoma City came roaring back in the third, outscoring Minnesota 32-18 to open up what turned out to be a decisive 76-66 lead heading into the fourth quarter.

Gilgeous-Alexander, who had a lethargic first half with 11 points after shooting just 2-of-13 from the field, led the Thunder recovery.

The Canadian point guard, who is vying for the NBA's Most Valuable Player award, rattled in 12 points in the third quarter while Jalen Williams added nine points to keep Minnesota pinned back.

Crucially, Oklahoma City's defense stepped up to shut down Randle's scoring rate while Minnesota star Anthony Edwards was kept scoreless in the fourth quarter.

Gilgeous-Alexander finished with 31 points, five rebounds and nine assists while Williams added 19 points with eight rebounds, five assists and five steals. Chet Holmgren added 15 points with Isaiah Hartenstein grabbing 12 points.

"Honestly we were a bit rusty in the first half but we shouldn't be," Gilgeous-Alexander told ESPN in an on-court interview.

"We were missing layups, free throws. We just needed to keep being aggressive and trust our work.

"We got downhill, the layups started to fall and we started making our shots and we started getting stops defensively."

- 'That can't happen' -

Gilgeous-Alexander acknowledged the best-of-seven series is only just getting under way though.

"Game ones are feel-out games. In game two they're going to make adjustments and we're gonna have adjustments. It's a series and it's best-of-seven, not first to one.

"It's a good start but there's a lot more work to do."

Randle led Minnesota's scoring with 28 points while Edwards, who suffered an injury scare after rolling an ankle, finished with 18 points, nine rebounds and three assists.

"We didn't have a lot of patience in the second half and then our offense didn't get a bunch of quality looks and it affected our defense," Timberwolves head coach Chris Finch said.

"And then when we did get good looks, they didn't go down. Our offense affected our defense, and that can't happen.

"When we got good looks, we couldn't really connect when the game was kind of turning against us."

Thunder coach Mark Daigneault said his team capitalised on being only four points behind at the break despite a lacklustre first-half offensive display.

"For us to play as poorly as we did in the first half and only be down four was a major victory for us at half time," said Daigneault. "Our defense was a huge catalyst."

The Thunder were pushed all the way in the previous playoff round, winning a titanic seven-game series against Nikola Jokic and the Denver Nuggets on Sunday.

Daigneault expects Minnesota to present a different challenge.

"They're a very different team stylistically. It took us a second to calibrate to the opponent but our defense allowed us the margin to do that."

Gilgeous-Alexander said Oklahoma City's defense had targeted Randle after his 20-point first half.

"We just tried to be aggressive with him, make him uncomfortable -- that's what you try to do with great players and we did that in the second half," Gilgeous-Alexander said.

"But if you want to be a really good team, you got to do it for all 48 minutes. But we'll take the 'W' (win)."

Game two of the series takes place in Oklahoma City on Thursday.