Thirty wins down, one to go.

The Beijing Ducks beat the Guangdong Southern Tigers 107-98 on Wednesday night at the MasterCard Center, claiming Game 4 of the CBA Finals to take a 3-1 lead in the best-of-seven series.

The Ducks can claim the first title in franchise history with a win on Friday night at home. If the Tigers win, the series returns to Guangdong for the final two games.

With much of Beijing's Chinese lineup either hurt or in trouble, its two American players shouldered the load. Playing to a chorus of MVP chants, Stephon Marbury had 28 points, 7 assists and 7 rebounds, while Randolph Morris continued his solid playoff run with 32 points and 12 rebounds.

The Ducks' Zhu Yanxi was taken away in an ambulance at halftime after writhing on the court for several minutes with what appeared to be a serious rib injury after getting tangled up near mid-court.

Marbury struggled in the first half, scoring five points in limited minutes, but came to life in the second once he and Morris were in the game.

"We knew that they were going to switch, so we were just patient and posted Mo against the guy who was guarding me," Marbury said. "As we posted Mo and they guarded him, he kicked the ball out so we had more open shots."

Guangdong hung close most of the game, but every time it started to get ideas about making a run, Beijing answered with eerie consistency.

Aaron Brooks led Guangdong with 28 points and 6 assists, while James Singleton had 22 points and 11 rebounds.

Officials were determined to keep Beijing's crowd in hand after it deemed fans had gotten out of control last week in Game 1.

The league threatened to move Game 5 to a neutral court, and a video played on constant loop before the game, with several players asking for the crowd to keep foul language to a minimum.

Several fans were escorted from the arena by security in the first half, but the crowd remained mostly civil, if rowdy.

Game 5 will be at the MasterCard Center on Friday at 7:30 pm.

Sun Xiaochen contributed to the story.

dustylane@chinadaily.com.cn