A few things to keep in mind as you watch Columbus and Portland go after it Sunday in Mapfre Stadium, where the 20th MLS Cup will be decided:

Nagbe and Trapp as the key midfield connectors

Two men central to Sunday’s action had their international coming out party about a year apart, both in interesting ways, although in very different settings.

Darlington Nagbe, the silky smooth Portland Timbers midfielder, earned his first US national team cap in St. Louis last month, and it really was quite a lovely moment. Nagbe, Liberian-born but having lived almost all of his 25 years in the United States, simply could not suppress a magnificent smile as he trotted onto the field, spilling over with pride for his first chance to represent the United States.

In the future, he could potentially share a US midfield with Wil Trapp, whose applications in the Crew midfield are equally as important as Nagbe’s to Portland. Trapp has been capped once but has yet to make a mark internationally. That doesn’t mean he hasn’t received some “international recognition,” so to speak. It came from the tongue of none other than Thierry Henry. Trapp was running the show late in 2014 as his Crew shredded the Red Bulls in New Jersey, and Henry was effusive in his post-game praise for the young midfielder.

Neither Nagbe nor Trapp are necessarily known for dynamic deeds, although Nagbe has more of that in his game, blessed with useful speed and having nailed a couple of wonder goals along the way around teeming Providence Park. Rather, it’s their sensible, skilled work through the midfield that allows all teammates nearby to be more proficient at their own jobs.

Nagbe may already be one of the most comfortable players on the ball in the US national team pool. Moments will be rare (if there are any at all) in Sunday’s final when Nagbe looks harried or uncomfortable receiving a ball, no matter what manner of chaos is unfolding around him. His ability to possess and progress is wonderful in its simplicity, and he’s doing more of it from central positions lately as manager Caleb Porter has moved Nagbe into the middle while toggling between 4-3-3 and 4-2-3-1 alignments.

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The formula often looks like this: Diego Chara covers ground and wins tackles as the man on a mission he is and then finds Nagbe, who can then find the roaming Diego Valeri, who can then deliver passes in good spots for striker Fanendo Adi. Finding the Timbers’ big target (he’s an absolute handful at 6-foot-4) in those happy spots is a great scoring chance waiting to happen.

Trapp’s role in Columbus’s equally tight and adept midfield is something similar. He’s frequently the connecting link between enforcer Tony Tchani and playmaker Federico Higuain. (Argentine playmakers; there’s a lot of that going around in MLS, eh?) The approach from there looks slightly different from Portland’s, as Higuain will look to find his able wingers, who spread the front line and then attempt to feed powerful 22-goal scorer Kei Kamara.

Trapp’s ability to smoothly, reliably manage possession makes Gregg Berhalter’s system work. Columbus wants to move the ball out of the back every time, and they usually can thanks to Trapp. Since the 22-year-old tempo setter is so good at his job, Higuain can stay further up the field, roaming similarly to Valeri, confident that Trapp will find him to get the process going.

Not sure whether Nagbe or Trapp will be the “next big thing” in US national team soccer; but what they do on the field can certainly be part of the Yanks’ plan.

Center backs, on the spot

The dirty work of stopping those big strikers is pretty critical to Sunday’s outcome. Center back play has been a critical element in both playoff runs.

The Timbers were breached just three times in four playoff matches against Dallas and Vancouver. Most recently, goalkeeper Adam Kwarasey was rarely stretched over two legs of the conference final against Dallas. He certainly would have had more tests but for Nat Borchers’ handy work, focused throughout and brave where needed. His big, emergency block late against Dallas’s Blas Perez probably saved his team from going into a white knuckle, extra time series-deciding 30 minutes.

His preferred partner, English veteran Liam Ridgewell, is hopeful a calf injury heals up in time. If not, Norberto Paparatto was mostly without flaw in replacement duty Sunday at Dallas, his assistance of left back Jorge Villafana critical and generally expertly timed.

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Opposite them, center backs Michael Parkhurst and Gastón Sauro give the Crew a useful balance. Parkhurst is better known – he’s been around MLS longer, has been in some US World Cup qualifiers, etc. – and his quality distribution is a perfect fit for Berhalter’s style. But it’s Sauro, with experience in South America and Europe, who has taken the Crew defense to another level. He’s more aggressive; whereas Parkhurst is better reading, anticipating, stalking, etc., Sauro will lean into his opportunities to come off the line of four and tackle.

Big strikers: a real handful for defenders

So the Crew will work to get Sauro matched up with Adi. If Adi can find himself backing into Parkhurst, he’ll have a better chance to win the physical battles and get something on the turn, just as he did for the first, critical road goal last week against Dallas. Adi’s 16 regular season strikes were tied for seventh best in MLS this year.

Both teams get lots of credit for their possession style, but in both cases, having a striker emerge as a forceful scoring presence pushed them past the final playoff mile.

Kamara was so dangerous for Columbus because his team’s wing play is so good (largely thanks to Best XI man Ethan Finlay), and because Trapp and Tchani are adept at big, switching balls out of midfield. When defenses get pulled apart, Kamara gets isolated near goal and good things tend to happen for his Crew. Which is why the Crew attempted more crosses in open play in 2015 than any other team, and by a long way.

And they say the true No. 9 is dead. Not so with Sunday’s sides at Mapfre Stadium.

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