The gross reason Warriors’ Gary Payton II wandered off court during Game 4

Gary Payton II showed heart while nearly losing his stomach.

The Golden State guard stayed in the game through a defensive possession even as he appeared to have a mouth full of vomit in the first quarter of the Warriors’ 104-101 Game 4 loss to the Lakers.

Payton was seen mysteriously wandering off the court after the Warriors got the ball.

A zoomed-in view of Payton showed his cheeks expanded to indicate the severity of the issue.

Apparently Draymond Green did not realize the Warriors were playing a man down.

The Warriors’ ensuing offensive possession ended when Green threw the ball directly to the Lakers bench, seemingly under the assumption there would be a player standing on the wing for an open 3-point shot.

Green shot a quizzical look to the Warriors bench afterwards.

Payton was added to the starting lineup ahead of Game 4, replacing JaMychal Green.

It was a surprising decision, considering Payton had started one game during the regular season and his playing time was on a downward trend since getting 27 minutes in Game 2 of the previous series against the Kings.

The news of the lineup change leaked out before the game, reported by The Athletic’s Shams Charania.

“That’s OK. Shams is in the lineup sharing business,” Warriors coach Steve Kerr said. “We have a special correspondent within the organization that shares information with him apparently.”

Despite apparently being a little under the weather, Payton was a bright spot for the Warriors.

The 30-year-old, who was acquired at the trade deadline from the Blazers, scored 15 points to go along with three rebounds and two assists.

However, it was not enough as the Lakers — thanks to a breakout fourth quarter from Lonnie Walker IV — held on for the three-point win in the back-and-forth battle.

“We got a lot of heart on this team, a lot of fight so back against the wall and we got to come out swinging,” Payton said afterwards. “We have a lot of guys right here that is ready and stay ready so we just got to come out and hit first.”

The series now shifts back to San Francisco with the Warriors in a 3-1 deficit and their title defense on the brink.

Game 5 is Wednesday night at 10 pm ET.