NEW YORK -- Adam Eaton called Mets third baseman Todd Frazier “very childish” after the two players had to be separated from one another following an on-field incident during the Mets’ 5-3 victory over the Nationals on Monday night at Citi Field.

Eaton said he heard Frazier yelling at him across the infield all night long, but it was after Eaton grounded into a double play to end the top of the third inning that he confronted Frazier near the first-base bag and Mets dugout. The two had to be restrained between innings, continuing what has been a years-long feud between the two former White Sox teammates. Both players remained in the game.

“I’m walking with my head down, play’s over, I’m walking away, I can still hear him,” Eaton said. “I’m a 30-year-old man with two kids, got a mortgage and everything. He wants to loud talk as he’s running off the field. At the end of the day, I got to be a man about it. I tried to stay patient with the childishness, but it is what it is. I got to stand up eventually.”

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Frazier did not elaborate on the incident after the game, saying, “It was nothing” when asked by reporters. When pressed about how the issue started, Frazier once again responded, “It was nothing.” Eaton, on the other hand, did not hold back.

“It’s funny,” Eaton said. “He didn’t really want to walk towards me, but as soon as someone held him back, then he was all of a sudden he was really impatient, like trying to get towards me. Just being Todd Frazier. What’s new?”

The bad blood between these two players dates back to 2016, when both Frazier and Eaton were teammates with the White Sox for one season and far from best friends. At one point during the season, they had lockers next to each other in Chicago’s clubhouse, but they were separated later in the season.

Whatever issues began then boiled over last season during a game on August 26 at Citi Field. A few Mets had taken issue with Eaton because of a hard slide into second base earlier in the month that wound up injuring Mets infielder Phillip Evans. Once again, Frazier started shouting at Eaton on the field during that game and the two exchanged words.

"I think there's a little bit of a history there,” Mets manager Mickey Callaway said. “And Fraz is an emotional competitor."

Eaton said he was surprised Frazier’s issues with him were ongoing, and he still did not understand why the issue developed between the two players.

The Mets and Nationals have nine more meetings with one another, including another showdown Tuesday night at Citi Field, meaning Eaton and Frazier are going to have to share the field with each other several more times.

“He’s one of those guys who always says it loud enough that you hear it but can’t understand it,” Eaton said. “So, he’s making a habit of it. I ignored him a couple times chirping coming across, but I had it to the point ... you got to be a man at some point. So, I turned around, had a few choice words with him.”