This is not Luis Robles' first Supporters' Shield chase. The New York Red Bulls' goalkeeper and his teammates won regular-season titles in 2013 and 2015, finishing as runner-up to FC Dallas a year later. So being in the hunt come autumn for what some consider the truest measure of a team's overall quality is nothing new.

What Robles struggles to recall is a higher-profile showdown than Sunday's meeting between league-leading Atlanta United and second-place New York at Red Bull Arena (1 p.m. ET, ESPN) -- or a direct challenger as fearsome as United is.

"It does feel different," Robles told ESPN FC, recalling 2013 Sporting Kansas City and 2015 Dallas. "I don't think there are many similarities. [Atlanta] really is, in my opinion, the standard. I have nothing but good things to say about that organization."

Atlanta, playing in only its second season in Major League Soccer, enters the weekend having scored 10 more goals than any team in the Eastern Conference.

It has a manager who has coached both Barcelona and the Argentina national team -- and is a hot-enough commodity to be linked with vacancies with both Colombia and Mexico -- and a goal scorer in Josef Martinez who has already shattered the league's single-season record. From attendance figures to infrastructure to raw ambition, as Robles said, this club is the standard bearer.

And yet the Red Bulls possess the one thing Atlanta wants and cannot yet have due to the sheer youth of the franchise: recent hard-won experience in the biggest games.

Bradley Wright-Phillips passes the ball during the New York Red Bulls' MLS match at Atlanta Untied. Rich von Biberstein/Icon Sportswire via Getty Images

Besides just those Shield runs, the Red Bulls reached the U.S. Open Cup final last year and the CONCACAF Champions League semifinals this past spring. Their recent -- well, entire -- playoff history has been littered with disappointments, but those can also be spun as scar tissue to harden the group for a deeper run in the near future.

Besides quality of opponent, there are additional contrasts to New York's other regular-season titleholders. The 2013 team, headlined by Thierry Henry, peaked late, and the '15 edition started fast before weathering a midseason rough patch.

"Both of them were fantastic runs, and in contrast to this year, we haven't really had that single run," Robles said. "We've just been good all season."

Their steadiness has been remarkable given the amount of potential turbulence. The Red Bulls went nearly as far as Toronto FC in the CCL but haven't been hampered by it like the Reds have. Head coach/philosophical guide Jesse Marsch left in early July to become an assistant at RB Leipzig.

"It feels like three seasons, because of the amount of stuff we've gone through," Robles said.

And yet, here they are, near the top of the league on the brink of October, as has become something of an annual tradition in Harrison, N.J.

"The first thing that comes to mind about what's similar is that with all three of those rosters," Robles said, "there wasn't an expectation around the league that a run like this was possible."

That sense of being constantly overlooked will provide the hosts with no shortage of motivation before Sunday afternoon -- as will the controversial absence of leading scorer Bradley Wright-Phillips. Wright-Phillips picked up a one-game yellow-card-accumulation suspension for swearing at a referee last weekend. the type of infraction one suspects might have been overlooked had it been committed by, say, Martinez as he seeks to build upon his record scoring tally on national television.

"There are certain players that just get the benefit of the doubt," Robles said, Wright-Phillips not being among them.

The English forward is a decent personification for this team as a whole: accomplished but rarely featured in league-wide promos. Suffice it to say that Atlanta, the marketing darling for MLS, does not have that problem.

"[That disparity] comes up in conversation," Robles said. "It's never the narrative. But it does come up, because you can't help but notice it."

Contrasts tend to make for compelling entertainment, and on that basis and many others, Sunday's Supporters' Shield showdown could very well end up as the league's game of the year.