The Lakers slipped to 0-3 after James, who joined the LA franchise this summer, missed with a potential game-winning three-pointer with less than three seconds to go.
James had landed a 3-pointer with 3.3 seconds of regulation time left to take the game into overtime after the Lakers had trailed by eight points with 70 seconds remaining.
But with the Lakers up by one with 13 seconds left in the game, James missed two free throws and he could not respond after Patty Mills had put the Spurs ahead with seven seconds left.
The Lakers were missing Brandon Ingram and Rajon Rondo, who were both suspended for their part in the melee during the defeat to the Houston Rockets.
Kyle Kuzma stepped up with 37 points while James ended with 32, but LaMarcus Aldridge’s 37 points and 10 rebounds helped the Spurs improve to 2-1.
The Golden State Warriors bounced back from their defeat on Sunday night with a comprehensive 123-103 victory against the Phoenix Suns.
Stephen Curry hit six three-pointers in his 29-point performance while Kevin Durant added 22 for the reigning NBA champions.
The Toronto Raptors are 4-0 after easing past the Charlotte Hornets 127-106.
Kawhi Leonard top-scored with 22 points for the Canadian side, who have earned three of their wins by a margin of more than 10 points.
Kyle Lowry added 16 points and 14 assists as every Toronto player who took to the floor scored some points.
The Boston Celtics, pre-season favourites in the Eastern Conference, fell to 2-2 after they were beaten 93-90 by the Orlando Magic.
Nikola Vucevic had 24 points and 12 rebounds for Orlando, who bounced back from two successive defeats to improve to 2-2.
Celtics duo Kyrie Irving and Gordon Hayward both had three-point attempts in the final seconds but neither were able to force the game into overtime.
The Milwaukee Bucks moved to 3-0 after seeing off the New York Knicks 124-113, with Giannis Antetokounmpo recording a 31-point haul and claiming 15 rebounds, while the Minnesota Timberwolves were 101-91 winners against the Indiana Pacers.
The Washington Wizards spoiled the Portland Trail Blazers’ night as the visitors won 125-124 after overtime.
Portland’s players had turned up for the game in Halloween costumes but they were unable to mark the evening with a victory in a thrilling finale.
John Wall missed two free throws for Washington with six seconds left but Damian Lillard’s attempted game-winning shot was blocked by Otto Porter Jr.
Elsewhere, Zach LaVine’s 34 points were in vain as the Chicago Bulls were beaten 115-109 by the Dallas Mavericks while the Memphis Grizzlies saw off the Utah Jazz.
For all the hoopla and hype the franchise has received in the past three months since adding the best player in the world, the Lakers are, as of right now, a flawed team.
That was very much proven in the 128-119 takedown by the Portland Trail Blazers on Thursday, which showcased the positive and negative aspects of Los Angeles’ identity.
Let’s start with the bad.
Perhaps the biggest criticism of how Magic Johnson built the team around James in the offseason – aside from mixing volatile personalities – was centered on the lack of shooting. James’ teams in the past have been at their best offensively when they’ve had shooters to space the floor for James, which has opened up playmaking opportunities.
On Thursday, the Lakers missed their first 15 attempts from beyond the arc and finished just 7-of-30 from long range. With the Trail Blazers not feeling threatened by Los Angeles’ shooting, the defence cramped the floor and made life difficult for the Lakers’ half-court attack.
There won’t be many nights when James, Brandon Ingram and Kyle Kuzma combine to go 1-of-15 on 3-pointers, but the concerns over shooting were validated in game one.
One player who had no problem knocking down shots was Josh Hart, who hit 8-of-12 from the field, including 3-of-5 from distance, for his 20 points off the bench. Hart made his case to start, but swapping him in for starting shooting guard Kentavious Caldwell-Pope – a 38.3 per cent 3-point shooter last season – may only improve the Lakers’ shooting marginally. Instead, the Lakers could look to use Hart in more small-ball lineups in which James plays centre.
However, that would just worsen Los Angeles’ other issue – their lack of interior defence and rebounding.
JaVale McGee got the start at centre and swatted three shots, but was on the floor for just 22 minutes as the Lakers tried to create more spacing without him in the lineup.
The downside of that was the Lakers getting outrebounded by a 54-46 margin, which included 14 offensive boards for Portland, leading to 21 second-chance points.
Los Angeles didn’t play any other true big man aside from McGee, but they’ll have to consider putting more size on the floor going forward, even if it means sacrificing half-court scoring.
That may be a trade-off worth making because there should be no shortage of points, thanks to the Lakers’ ability to strike in transition.
Even disregarding the runaway train that is James in the open court, Los Angeles are stocked with ball-handlers, playmakers and youth – ingredients that give them one of the most potent fast-break attacks in the league.
That was evident on Thursday as the Lakers sprung for 34 fast-break points in a game that featured a breakneck pace of 113.5 possessions.
Some discrepancy between pace statistics on https://t.co/HbzTMXqxMf and Basketball-Reference. But still.— Adam Fromal (@fromal09) October 19, 2018
Fastest-paced games of LeBron James' career:
1. 10/18/18 vs. POR: 113.5 via https://t.co/HbzTMXqxMf
2. 3/13/18 vs. PHO: 113.1 via B-R
3. 1/6/17 vs. BRK: 109.3 via B-R
Los Angeles want to run early and often, and when they get an opportunity to push the ball, it’s likely to result in points. That’s the biggest strength of the team right now and it’s one that will give them a chance to compete on a night-to-night basis while they work through their weaknesses.
The pace they want to play with will also result in some high scores, but that won’t necessarily be an indictment of their defence.
Even though the Trail Blazers scored 128 points, they shot just 44.0 per cent as the Lakers were hurt by their inability to finish off possessions with a rebound and their general effort at times.
It’s only one game, but it revealed exactly what the Lakers are.
The wait is over. LeBron James will play his first regular season game with the Los Angeles Lakers on Thursday, which will begin the next phase of his legendary career.
A three-time champion, LeBron will aim to restore one of the most prominent franchises in team sports back to glory and continue to add to his legacy as one of the greatest players of all-time.
Check out how James’ next chapter affects those around him in the video below.