HANOVER, N.J. — Goalkeeper Luis Robles points to former coach Jesse Marsch’s tirade, while defender Tim Parker speaks of trash talk on and off the field following the last regular season meeting.

Whatever it is that provided the spark, it appears the New York Red Bulls-Philadelphia Union rivalry is ready to bubble over with a first Audi MLS Cup Playoffs meeting coming in Round One Sunday (3 pm ET | FS1, FOX Deportes in US; TSN4, TVAS2 in Canada) at Talen Energy Stadium.

“It's a game in the playoffs where there's a lot on the line that can fuel a rivalry,” Robles said. “Everyone in our locker room, we know what to expect — a very good team that's been well-coached all season long, that is going to bring the right mentality and physicality to the game. And we have to match it. And if we match it and put the game on our terms, it bodes well for us.”

Of the 31 all-time meetings between the Red Bulls and Union, five have been in the U.S. Open Cup, but Robles said those games were sparsely attended. He knows it will be different Sunday.

“Philadelphia is a really fun place to play, the atmosphere that their supporters bring, that our supporters bring really makes it feel that there's something exciting to play for,” Robles said. “Now you factor in the playoffs, and it's going to make it all that more exciting.”

Robles chuckled when remembering Marsch tossing a few soccer balls after being ejected for complaining about some referee decisions. Parker said the last meeting between the teams, a 2-0 Red Bulls win at home in September, had that bite the best rivalry matches have.

“There was a lot of jawing during the game, a lot of jawing after the game. We got the result and that’s what mattered to us but there was a lot of talking going on during the game and after the game," said Parker.

In the Red Bulls locker room after, Kemar Lawrence was asked about Fafa Picault’s complaints to the officials.

“That’s my job, to frustrate wingers and I like that,” Lawrence said. “He’s not going to outrun me ever so if they want to play in behind, fine, if they want to play to his feet then I’ll face you up and I’ll defend.”

Because of the Red Bulls’ confrontational and combative style on the field, Union coach Jim Curtin called RBNY “bullies” leading up to the game.

“If you punch the bully in the nose, a lot of time it backs down,” he said in a radio appearance on “The Daily Ticket With Sean Brace.”

“I've never been called a bully before,” Robles said. “Maybe he's looking for bulletin board material, I’m not really sure, but we really respect them. But there's that fine line where you don't want to give them so much respect and all of a sudden, you’re a bit timid when you approach them.”

Red Bulls coach Chris Armas also laughed about Curtin’s statement, and joked he “might have to chase Jim around a little like I did back in the day.”

“I think Jim has a lot of respect for our team and what we do and we do to them,” Armas said of his former Chicago Fire teammate. “In terms of bullies, like when you think of a bully at the schoolyard I mean listen, I think he knows we're aggressive, and it's important for our style of play, and we know that they'll be the same. Two bullies will be going after it.”

Parker, a diehard New York Giants fan, loves the idea of going to Philadelphia and getting a win. If it gets physical, so be it.

“I don’t consider ourselves bullies,” Parker said. “But if they want to see if they throw the first punch, then we’ll see who gets there first.”