Friday night's Padres-Giants game in San Francisco was briefly delayed after two baseballs were thrown from the left-field bleachers in the direction of San Diego outfielder Jurickson Profar.
The veteran utility man called timeout and huddled with umpire Ted Barrett to talk it over.
Profar seemed to be pointing toward which fan or fans may have been the culprit.
"I think Profar may have a pretty good idea where that ball came from," said Giants broadcaster Mike Krukow.
After the game, Profar told reporters that he threw a between-innings warmup ball to a Padres fan in the stands, but it was intercepted by a Giants fan and thrown back onto the field.
"I think he missed it and some Giants fan caught it and then when I turned around ready for the pitch to be thrown, he threw it back and almost hit me. I threw it back and then they started throwing more."
It was unclear where the second ball came from.
Later in the game, it appeared fans had thrown beer cans at Profar.
Profar denounced the classless display.
"You pay to watch the game, you can talk ... but as soon as you try to throw stuff, that's different."
The ugly incident comes just weeks after Yankees fans targeted Cleveland Guardians outfielders with beer cans. Several Yankees players, including star slugger Aaron Judge, took to the outfield to tell the fans to stop.