In a 12-second video posted on social media, Rendon grabs the fan by the shirt through the guardrails and accuses the fan of calling him a "b----." Rendon continues to challenge the fan as he denies the claim. Rendon then calls the fan a "motherf---er" and takes a swipe, which does not connect, as he lets go of the shirt and proceeds to leave the area.
No video showing what led to the altercation was immediately available.
"We are aware of the video and we are now looking into the matter," MLB said in a statement.
Rendon told reporters Saturday that he could not discuss what happened due to MLB's investigation. The Angels had said Friday that they had no comment on the situation, and general manager Perry Minasian and manager Phil Nevin both said Saturday that they could not comment as well.
Rendon was 0-for-3 in the Angels' 2-1, Opening Day loss to the Athletics. He missed the majority of 2022 after undergoing right wrist surgery during the season.