LeBron went down in the third quarter with the problem and was heard on court saying: “I heard a pop.”
However, after the match it was confirmed the muscle is intact but the extent of the damage is unknown.
Lakers coach Walton therefore confirmed LeBron will undergo an MRI scan to discover the extent of the injury.
The NBA superstar is therefore likely to miss the match against the Sacramento Kings on Friday at 3am UK time.
LeBron has played in every game for the Lakers this season after moving from the Cleveland Cavaliers.
And that’s after the 33-year-old appeared in all 82 regular season games last year.
LeBron suffered the injury when reaching down for the ball and losing his footing.
He immediately started moving gingerly and had to be replaced as he returned to the dressing room and played no further part.
LeBron’s team-mate Josh Hart says the Lakers are ready to step up if he can’t play for a series of games.
“Obviously we hope he’s okay but we’ve got a lot of good players.
“If he’s down we’re ready to step up.
“None of us are scared of the spotlight.”