A blue wall along the northwest corner of Children’s Mercy Park highlights Sporting Kansas City’s top achievements. It’s a constant reminder that the past handful of seasons have featured some celebratory moments. In that vein, there’s mention of the 2013 MLS Cup championship and two more U.S. Open Cup titles.

But while the number of trophies might classify as a bit of a rarity in the growing MLS, a detail not written on the wall is much more of an anomaly — the uniformity of the group that has accomplished the feats.

A roster that has been constantly trimmed along the edges over the last four seasons has kept its core intact. And it will open yet another playoff battle Thursday, when Sporting Kansas City faces Seattle at 9 p.m. on the road in the Western Conference knockout round.

But as the postseason arrives in 2016, it possesses a bit of a unique underlying theme: Might this be one last hurrah for the current group?

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“The guys that have been here for whatever it is — four or five years — might not be here next year. Or some of us might not be here and some of us might,” midfielder Benny Feilhaber said. “I don’t think we think that far ahead. But having said that, we know (these playoffs) are the last time we’ll all play together — these 20 or 30 guys that have been here this year. So we’ll try to make the most of it.”

It’s always reasonable to expect roster turnover, Feilhaber explained, regardless of the results from the previous season. But there’s a consensus within the organization that the 2016-17 offseason could feature an abundance of it — that perhaps even the core bunch could be affected this time.

Sporting KC has six players on the roster who have averaged at least 20 appearances over the past four seasons — Feilhaber, Matt Besler, Graham Zusi, Seth Sinovic, Dom Dwyer and Jacob Peterson.

Feilhaber is out of contract after the season. MLS will welcome two new teams into the league, prompting an expansion draft in which Sporting KC could lose a key player. And coach Peter Vermes has expressed the need to “close the gap” with the high-dollar clubs, which could limit other options in a salary-cap league.

Asked if he has already considered how his roster might look in 2017, Vermes said, “I think you’re always in this business looking to improve your team. I don’t think that ever stops.”

In other words, for the first time since Sporting KC lifted the 2013 MLS Cup, the offseason could be marked more by uncertainty and less by shoring up holes.

That’s one way to view it. On the other hand, if change is indeed coming — and that remains an “if” — then the 2016 postseason presents one final, go-out-on-a-high-note opportunity for a collection of players who have enjoyed their best seasons in Sporting KC uniforms.

“You honestly don’t really reflect on big-picture stuff like that until after it’s done,” Sinovic said. “Hopefully the thought (Friday) will be what we need to do to get ready for Sunday.

“We’re in the moment right now. We have to be able to focus on the game because we know what it takes to win these games.”

And therein lies the primary advantage of the aforementioned consistency. Even without an MLS playoff victory over the past two seasons, this is a playoff-tested group. In a season in which both returning MLS participants did not even qualify for the postseason, Sporting KC is back in the tournament for the sixth straight year.

“It’s something we should be proud of, but I know this group in particular, we definitely want something more,” Besler said.

They’ve done it before. And there’s a sense the same group will have another opportunity.

After tinkering with his lineup throughout the season, Vermes has opted for a return to the familiar. On Sunday, when the club clinched its playoff spot, six members of the starting lineup were also starters in the 2013 MLS Cup final against Real Salt Lake.

“We’re definitely not reflecting (on it) right now, but we all know what we’ve done,” Feilhaber said. “With the experience that we have, regardless of what place we finished in the regular season or who we’re playing against, we know we have the capability of making a run.”