The sixth inning became more than just a contest between Triple-A Buffalo and Syracuse on Thursday night at NBT Bank Stadium. It became a battle of brothers on the mound.

Cole and Beau Sulser only played together for one year at Dartmouth College in 2013 as Beau entered his freshman year while Cole stayed as a fifth-year senior. But the siblings had never played in the same game professionally until Thursday night, when Beau's Bisons took the 8-4 victory over Cole's Mets.

The stars aligned for the two brothers after Beau signed with the Blue Jays earlier this season and the Mets optioned Cole to Syracuse on May 8. When parents Roy and Pixie Sulser found out there was a week in which the two brothers' teams were meeting, they made the trip to Syracuse along with Beau’s wife, Jennah.

“I'm sure it was a really cool moment for them," Beau said. "And a proud moment to see that ... their sons, they still think of us as being their little kids -- and we're 30 and 34 -- getting to live our dream and getting to do it together.”

“To just have a moment where we're actually competing against each other, and it's not just theoretical, was really cool,” Cole added. “Me and my brother have always talked about it and joked about it, and it's kind of crazy that after -- I guess this is the seventh year that we're both playing professionally -- that it finally lined up to play against each other and then pitch in the exact same game and the exact same inning."

Beau entered the game first and retired the side in order in the bottom of the fifth inning as Cole watched from the bullpen, preparing to enter in the sixth.

“It was a very unique situation,” Cole said. “It's one of those things that ideally, you want to be as locked in to the moment, [with] what you're supposed to go out there and do, as possible. But I have to admit, it was a little distracting knowing that my little brother's pitching on the other side against us.”

In the visitors' dugout, Beau pretty much felt the same way.

“You know, the first inning I came in and I was definitely attacking,” he said. “(Cole) hadn't come in and pitched yet and so I definitely felt more settled ... but it really is tougher to watch him than it is to pitch up there myself. Just because you feel like it's not in your control.”

Beau's feelings were evident in the sixth after he gave up a three-run homer to Luke Ritter. The right-hander was actually more concerned about his brother's reaction than his misstep.

“That's not ideal, but I can handle it in terms of, you know how you're feeling mentally. But for your brother you're like, 'How is he handling it? How is he doing?"... It was awesome, one of the coolest experiences but definitely not the most relaxed half inning when I wasn't pitching.”

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Cole, who completed 1 2/3 scoreless innings on a hit and two walks with two strikeouts, had the same feelings watching his brother pitch. On top of that, there was the added pressure of watching teammates actively cheer against their family.

“You know, everybody was asking like, 'Hey, so, when he's facing me? Are you going to be rooting for him or me? I'm on your team,’” said Beau. “And I was like, 'Oh, unfortunately, man, I'm gonna be rooting for my brother.'

“The one thing that was interesting was, when he walked somebody and your whole dugout is cheering and happy that they walked, and a part of you is like, 'Couldn't you have just grounded out?' It was a really interesting dynamic for the first time because obviously we've never experienced that.”

The brothers met again on Sunday in a 7-1 Mets victory, but did not face each other in the same frame. Cole pitched a perfect top of the sixth while Beau yielded home runs to Carlos Cortes and Brett Baty in the eighth.

But the outcomes wound up being almost besides the point, especially when they had a chance to come full circle and play catch together before Saturday's game.

“I'm trying to learn a sinker, and he had a grip that a guy on his team was working with," Beau said. "He came over and showed me and so one thing led to another, and I was like, 'Well, let me throw you a couple' and so we ended up playing catch a little bit at the end of their batting practice. So I think the big takeaway for me is just kind of lucky we are.”

“I think overall, it was just a really cool experience that we never knew if we would ever have the opportunity to actually get to do,” Cole added. “To be able to see it kind of come full circle, from being little kids playing on Little League fields to now facing each other in Triple-A years later, years into our professional career was just a really cool experience.”