By David K. Li NBC News

The history-making moment came days after Rachel Balkovec began her managerial career calling the shots for a New York Yankees farm club.

Alyssa Nakken coached first base for the San Francisco Giants on Tuesday night, making her the first woman to ever make an on-field appearance in a regular season major-league baseball game.

First base coach Antoan Richardson was ejected from the game before the Giants came to bat in the bottom of the third inning at Oracle Park in San Francisco.

That’s when Nakken, an assistant coach, was summoned for the groundbreaking moment. The ejection came with the Giants leading the San Diego Padres, 10-1, as San Francisco cruised to a 13-2 victory.

“I was prepared for this moment,” Nakken said. “Never knew if or when it would happen, but (I) was ready to step in when the team needed me to. So yeah I think it means a lot. It’s a fun start to the season so far.”

The coach said Tuesday night’s unplanned action gave her an insight to what it means for players who are not in the starting lineup, but have to be ready for action.

“Now I know exactly how our pinch hitters feel when (Giants bench coach) Kai Correa comes down to the cage and tells them to get ready,” Nakken said. “That’s just a great feel for me to have to understand what our players go through.”

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