We all know the metaphor about sliding doors, right?

Windows of opportunity can be fickle and fleeting, especially amid the moving parts and constant evolution of MLS. Even the most overpowering XIs and elegantly-constructed rosters are subject to change, with limited notice. Dynasties are hard to pull off around here.

Which brings us to one of Week 10’s most enticing matchups, LAFC’s visit to Children’s Mercy Park for a Saturday afternoon duel with Sporting Kansas City in front of a national ESPN audience (5:30 pm ET | ESPN, ESPN Deportes).

These are two standing members of the Western Conference elite, led by big personalities who have meticulously constructed a holistic, proactive ethos designed to win things, and to do so with panache. Both want the ball, averaging more than 500 passes per game this season. Both like to press, and throw numbers forward, preferring to vanquish opponents rather than merely outlast them.

And both have a clock ticking over their shoulders, with sliding doors and windows looming.

If you’ve perused the Transfer Tracker section lately, you probably know where I’m going. After the long, slow burn of his adolescent apprenticeship, Sporting’s teenage sensation Gianluca Busio is enjoying a breakout campaign, and his ranks of European suitors have taken notice. The hunt has quickened; the right transfer offer could sweep him off the plains and onto an eastbound plane at any moment.

Meanwhile his elder teammate Johnny Russell has been the linchpin of KC’s attack since his arrival in 2018, and now 31, finds himself in the final year of his current contract. Sporting’s run of four major trophies in the six years before he hit town? That trail has gone cold. Will the Scot root down in Kansas City, or return to the Old World to ramp up his national-team ambitions? What knock-on effects might the captain’s departure trigger?

When LAFC hoisted the 2019 Supporters’ Shield, it appeared the first of many such achievements, a dominant side still on the rise. As carefully as Bob Bradley, John Thorrington & Co. built that machine, and as much as they planned on a certain level of turnover, a crossroads seems to be approaching fast.

Diego Rossi and Eduard Atuesta are drawing overseas transfer interest comparable to Busio’s, and the shelf life on those kind of opportunities is limited. The likes of Mark-Anthony Kaye and Diego Palacios may well look in that direction, too. The long-delayed World Cup cycle is also a factor, finally underway as Qatar 2022 rapidly approaches.

This tenuous dynamic is becoming part and parcel of this league’s upper crust. Most of the aforementioned talents arrived in their current locales with the understanding that it wouldn’t be permanent, that MLS could help vault them on to other challenges. Making the most of what you have, when you have it, is becoming a vital skill here. And fans of all stripes would be wise to catch these talents while they can.

June is almost over. It’s not too soon to lay down markers for the crunch times ahead. Currently second in the West, SKC have enjoyed a more vigorous start to 2021 than their Californian guests, and they’ll feel compelled to keep that pace given the heft of their home-field advantage. Sporting are undefeated (4-0-2) at CM Park this year, while Los Angeles have yet to win on the road, a factor in their midtable plod.

Wednesday’s 2-0 home win over FC Dallas brought LAFC back to .500 (3W-3L-3D), and with Carlos Vela seemingly fit and firing again, it feels like a level set, like they can finally shift through the gears and regain the stride that they’ve only shown in flashes since that Shield capture. A humid summer afternoon in Kansas – with prairie thunderstorms in the forecast – presents a good chance to show it.