Houston Astros star Yuli Gurriel has escaped a World Series suspension for a racist gesture toward LA Dodgers' Japanese pitcher Yu Darvish, but he will serve a five-game ban next season.

After hitting a home run off Darvish to put the Astros ahead of Los Angeles early in Friday's game three, the 33-year-old Cuban was caught on camera using his hands to make a slanted-eye gesture while in the dugout.

"There is no excuse or explanation that makes that type of behaviour acceptable," said MLB commissioner Rob Manfred at a news conference after announcing the penalty before Saturday's Game Four in Houston.

Manfred said part of his decision to not suspend Gurriel during the World Series was because he felt it was unfair to punish the other Astros players.

"I understand that people may have different views," he said. "But it was my best judgment that this timing was appropriate.

Manfred met with Gurriel, who apologised after the game, and said the Astros first baseman reiterated his remorse and assured the commissioner that he would be offering a private apology to Darvish.

As part of the punishment, Gurriel will undergo sensitivity training during the offseason while the Astros, in a gesture of support, have agreed to donate Gurriel's salary for the five games to charitable causes.

After the game, Darvish called the gesture by Gurriel disrespectful but said he still respected his opponent and that everyone should use it as a learning opportunity.

"He has handled this entire difficult situation in an exemplary way," Manfred said of Darvish. "Especially noteworthy is his expressed view that we should all use this negative incident as an opportunity for learning and deeper understanding."

Dodgers manger Dave Roberts said he was happy that Manfred dealt with the issue swiftly so that the focus can get back to playing baseball.

"The way that it was dealt with I support. The way that Yu responded ... I completely commend him, support him, echo his thoughts that we need to learn from this. It's obviously not acceptable," said Roberts.

The Dodgers tied the series at 2-2 in Houston on Sunday [AEDT] with Joc Pederson's three-run shot in the top of the ninth inning helping them to a 6-2 win.

With the game four scores tied at 1-1, the Dodgers got their noses in front through Cody Bellinger's run-scoring single before a sacrifice fly from Austin Barnes scored another.

Pederson then smashed a homer to right field to give the Dodgers a five-run lead and silence the home crowd on Saturday night.

With the Astros down to their final strike, Alex Bregman homered but it proved too little too late as their unbeaten home stretch in the post season ended at seven games.

Reuters with AAP