James limped off the court with under six minutes remaining and did not return, wincing in pain and grabbing his groin area. The Lakers said at the time he was experiencing "left leg soreness".
The four-time MVP, who scored 30 points in the game, confirmed that the issue will need medical evaluation.
"I feel good besides for the injury," James said. "I'll get pictures on it tomorrow and go from there.
"But I didn't do anything extreme on the play, it was just when I landed I felt a little spasm or strain in my groin.
"Immediately I came out after the next play down I went to the free-throw line."
James missed 17 straight games during the 2017-19 season with a left groin tear, but he insisted this is "not as bad".
The loss left the Lakers with a 2-9 record, having lost four straight games by double-digit margins, and being without James for a stretch would be a major dent to their hopes of pushing back into contention for the playoffs.
Lakers head coach Darvin Ham did not want to speculate on the severity of the injury but admitted there was a balance to be struck in his recovery given the urgency of their situation.
James added: "In order for you to be productive for your teammates you have to take care of your body."
The 37-year-old is averaging 24.3 points, 8.9 rebounds and 7.1 assists per game this season.