Defending champions Milwaukee Bucks tipped off their NBA title defense in style as they beat Brooklyn Nets 127-104, while LeBron James' Los Angeles Lakers were outperformed by the Golden State Warriors on Tuesday.

The Bucks' Giannis Antetokounmpo scored 32 points, picking up where he left off in guiding them to victory in the NBA Finals last season. His emphatic all-round offensive display included 14 rebounds and seven assists.

The two-time NBA Most Valuable Player (MVP) was one of five Bucks who cracked double figures on a night when Milwaukee's fans celebrated as the team raised its first championship banner in 50 years at the Fiserv Forum.

Khris Middleton had 20 points while Pat Connaughton also made 20 off the bench. Jordan Nwora added 15 points while Jrue Holiday, who left the game with an injury early on, had 12 points.

Antetokounmpo was pleased with the way the Bucks turned their attention to the challenge of the Nets after the pregame festivities.

"It was hard – we all were excited to get the rings, and seeing our banner," Antetokounmpo said.

"It's kind of hard to balance that, to go from that excitement and emotional state to go and play a game.

"But I think we did a great job. We were able to focus on our game plan and ourselves and get a win.

"We've got a deep team. Everyone's ready to step up and ready to play. We play hard and play together," explained Antetokounmpo.

It was a chastening loss for Brooklyn, who have started the season without the services of Kyrie Irving.

'It wasn't good'

The Nets have left Irving out of the line-up for the foreseeable future because of his refusal to take the COVID-19 vaccine, which makes him ineligible for home games in New York due to city laws.

In Irving's absence, Kevin Durant led the Brooklyn scorers with 32 points while James Harden had 20. New signing Patty Mills added 21 – making seven-from-seven from 3-point range – while Nic Claxton had 12 points.

"It wasn't good obviously," Nets coach Steve Nash said, "We weren't as sharp as we needed to be, we weren't as physical as we needed to be, we weren't as organized as we needed to be.

"We just didn't play well tonight."

In Tuesday's other season-opener, the new-look Los Angeles Lakers suffered a humbling 121-114 loss to the Warriors at the Staples Center.

James led the Lakers scorers with 34 points while Anthony Davis chimed in with 33.

But the Lakers stars were the only two Los Angeles players to make double figures, while blockbuster new signing Russell Westbrook was restricted to eight points, five rebounds and four assists.

Instead, it was the Warriors who looked the more cohesive unit, with Stephen Curry leading the way with 21 points, 10 rebounds and 10 assists – Curry's first triple-double since 2016.

"This is a good feeling," Curry said. "We had a lot of excitement coming into this season – a new cast of characters mixed with our core.

"We weathered the storm tonight. I played like trash – shot the ball terribly – but if we can win a game like that where we just stuck with it defensively, it's a good omen for us."

Six Warriors players made double figures, with Jordan Poole just behind Curry with 20 points.

The Lakers led 59-53 at halftime but were blown away by the Warriors after the break.

Lakers coach Frank Vogel said his team remained a work in progress but was heartened by the scoring of James and Davis.

"Those two guys were spectacular," Vogel said. "We're going to be pretty good if we get those types of performances. We just have to be better defensively.

"This is a team which is all new to each other. Everyone is finding their way a little bit, and each day they're getting a little bit better."