FC Dallas are the lone remaining unbeaten in MLS. But unlike most of their peers at the top of the table, there’s a general sense that we still have a lot to learn about head coach Oscar Pareja’s group.

Most of the other top teams in the league – New York City FC, Atlanta United, Sporting Kansas City, Toronto FC and the New York Red Bulls, to name a few – all have relatively defined identities and clear groups of standout players. We know how to think about them and we have a rough feel for their ceilings, at least for now.

FCD are more enigmatic. They traded away a fringe US national team center back in Walker Zimmerman this winter and preseason No. 1 goalkeeper Jesse Gonzalez has yet to play a minute in MLS, but they’ve allowed the fewest goals in the league. They moved star attacker Mauro Diaz to the bench and shifted away from their trademark 4-2-3-1 formation, then went out and won their next two matches. They’ve tinkered to a level normally reserved for struggling squads, but they’re 3-0-3 heading into Sunday’s contest at NYCFC (6:30 pm ET | TV & streaming info).

“I think maybe just because we have coached with and we have played with a majority of this group for many years, that people recognize FC Dallas for certain characteristics,” Pareja told MLSsoccer.com earlier this week. “I know you all like to have a clear picture about FC Dallas, but I don’t know if you have that picture yet.”

The lack of clarity around FCD can partially be put down to unheralded players making big contributions, as a few of the team’s big guns have gotten off to slow starts.

Midfielder Jacori Hayes and goalkeeper Jimmy Maurer are leading the charge of under-the-radar players who have performed well out of the gates. Now in his second year out of Wake Forest, Hayes has started all six of FCD’s MLS games after appearing in just three last season. The 22-year-old defensive midfielder has been one of their best players, covering a ton of ground, remaining disciplined with his positioning and distributing the ball well while recording a goal and assist. The 29-year-old Maurer has perhaps been an even bigger revelation, playing like one of the top goalkeepers in MLS after joining FCD this winter following five years in NASL.

Their performances have paced FCD while Gonzalez and USMNT midfielder Kellyn Acosta have missed all six MLS matches due to injury and higher-priced, higher-expectation players like Diaz, Carlos Gruezo and Maxi Urruti haven’t fully kicked into gear.

There are also bigger questions about how those players might fit into Pareja’s new tactical setup. The manager shifted out of the 4-2-3-1 he’s used for most of his FCD tenure a couple of weeks ago, moving Diaz and Gruezo to the bench and starting Cristian Colman in front of Urruti in a two-forward setup for the club’s April 14 match at New England. The change worked. FCD sat deep, kept a clean sheet and got a winner from Hayes in their 1-0 victory.

Pareja kept the same formation and largely the same personnel for FCD’s return to Frisco last Saturday against Philadelphia. Diaz once again started on the bench, where he was joined this time by Urruti. He was replaced in the XI by Santiago Mosquera, who started on the wing and pushed leading scorer and assist man Roland Lamah to second forward. The lineup created plenty of chances in the opening hour, but didn’t break through until after Diaz and Urruti came on in the second half. Both Argentines scored, the ideal response to their benching and enough to give Dallas a 2-0 win.

“It’s a different look for us,” Pareja said. “It’s having somebody [in Colman] who can pin the center backs higher, that looks more dominant in the box and then to start all of the midfielders, that just makes you play more direct and probably with sequences that are more simple and not as elaborate as we normally do.”

Pareja praised their responses, but the new setup creates a touch of uncertainty around how Diaz and Urruti will fit if FCD continues in a 4-4-2. Does Diaz provide enough defensively to play as one of two central midfielders? Can Urruti coexist with Diaz without dropping so deep that he gets in the way of the No. 10?

Meanwhile, the form of Hayes, Maurer and Victor Ulloa has kept Gruezo pinned to the bench and could keep Acosta and Gonzalez from immediately reclaiming their starting roles once they’re fully healthy.

That uncertainty makes FCD a bit tough to pin down just now. But that’s not necessarily a bad thing. Giving run to Hayes, Maurer, Ulloa and Colman has shown Pareja that he has some quality depth to play with. Successfully tweaking his formation has given the Colombian a few solid looks to roll out later in the year. That’s hugely important, especially for an FCD team that faded badly down the stretch in 2017, struggling with poor form, stale tactics and a lack of competition in the squad as they failed to make the playoffs for the first time since Pareja took over in 2014.

They may be a bit of a mystery for now, but some uncertainty in April could lead to a promising summer and fall in Dallas.