The Houston Astros were involved in a bench-clearing incident for the second time this season on Sunday after Oakland Athletics batter Ramon Laureano was hit by a pitch and charged the dugout.
The Astros, who were found guilty of an elaborate cheating scandal during their 2017 World Series-winning season, had already been involved in a stormy clash with the Los Angeles Dodgers last month.
On Sunday, Athletics centerfielder Laureano lost his cool after being struck by a pitch from the Astros' Humberto Castellanos during the seventh innning.
Laureano appeared to take umbrage at some remarks shouted from the dugout by Astros hitting coach Alex Cintron.
Laureano removed his helmet and sprinted towards Cintron, prompting a prolonged melee involving multiple players from both sides.
The flashpoint will almost certainly lead to lengthy suspensions. Dodgers pitcher Joe Kelly was banned for eight games after his fiery display against the Astros last month.
Kelly had triggered a bench-clearing standoff after appearing to aim two pitches at Astros batters.
Major League Baseball has warned teams against physical confrontations this year, citing the risks of COVID-19.
Players across the league had voiced their frustration at the punishment meted out to the Astros over their sign-stealing cheating scandal.
The revelations stunned the world of baseball, and ultimately led to the suspension and dismissal of Astros general manager Jeff Luhnow and field manager A.J. Hinch. The team was also fined $5 million (4.24 million euros), the maximum allowable under MLB rules.
MLB commissioner Rob Manfred resisted calls to strip the Astros of the title, however, and also failed to levy punishments against multiple Houston players who admitted their part in the cheating plot.