Bruce Arena is unbeaten since beginning his second tour as U.S. coach: 9-0-5, including a 2-0-2 mark in World Cup qualifiers. (Mike Lawrie/Getty Images)

HARRISON, N.J. — The U.S. men’s national soccer team needed nine months, a coaching change, a few roster adjustments and a harrowing match in Mexico to restore hopes of qualifying for the 2018 World Cup in Russia.

And as the two-year exercise rounds the final turn, captain Michael Bradley said, “We’ve got to make sure we finish the job.”

After starting the competition with two defeats last year, prompting Jurgen Klinsmann’s ouster and Bruce Arena’s appointment, the Americans are third in a six-nation competition for three automatic berths. They have four matches left, starting Friday against second-place Costa Rica at Red Bull Arena.

Since Arena’s second tour as head coach began last winter, the United States has gone 9-0-5, including 2-0-2 in qualifiers and a Gold Cup championship, while regaining the chemistry and character that had gone missing in Klinsmann’s final days.

But for all the strides they’ve made, the Americans remain in a precarious situation because of the slow start. One false step Friday could swiftly alter their outlook ahead of Tuesday’s visit to Honduras.

“We’ve gained ground [since last fall], but there’s still four games left,” Arena said. “Clearly, tomorrow’s game is critical if we have any hopes of qualifying for this World Cup.”

The U.S. delegation has tossed around the “must-win” phrase. And although the Americans are, by no means, in danger of being eliminated from contention and could restore their place by winning on the road next week, there is some truth to Friday’s victory mandate.

World Cup qualifying in the CONCACAF region is full of pitfalls on the road, uncertainty that leaves teams targeting three points in every home date. Since opening with a 2-1 defeat to Mexico in Columbus, Ohio, and an embarrassing 4-0 loss at Costa Rica, the Americans have thrashed Honduras, 6-0, in San Jose and handled last-place Trinidad and Tobago, 2-0, in suburban Denver. A 1-1 draw at front-running Mexico, as well as a 1-1 finish at Panama, also bolstered the cause.

If they win Friday and claim at least a draw in Honduras, they’ll set themselves up to clinch a World Cup berth Oct. 6 against fourth-place Panama in Orlando. The United States could secure a berth next week — unlikely but possible — with two victories and several other results in the group playing out in their favor.

Home has been historically kind: Between a 2001 loss to Honduras in Washington and the Mexico setback, the Americans were 30-0-2.

The U.S. Soccer Federation’s choice of Harrison, home to MLS’s New York Red Bulls, came as a surprise. Although the federation arranges advance ticket sales for registered U.S. supporters and MLS season ticket holders, the metro area’s demographics could provide a bipartisan audience at the 25,000-seat gem across the Passaic River from Newark.

Asked about the USSF’s attempts to control the crowd breakdown, New Jersey-born goalkeeper Tim Howard said with a laugh: “It won’t be controlled tomorrow. That’s the beauty of our country — that it is incredibly diverse.

“Growing up in this area and knowing all the ethnicities and nationalities that are here, it will be wonderful. If it’s pro-Costa Rica or pro-U.S., it doesn’t really matter. It’s still our home. That’s what makes America beautiful.”

Despite New York’s rich history, the USSF has never before scheduled a qualifier in the New York area.

Asked about the first qualifier here, Brooklyn-born Arena said with Brooklyn humor: “This is New Jersey, by the way. The New York guys never accept the fact that New Jersey is New York.”

Regardless of crowd ratio, the Americans feel good about their on-field direction since the two early defeats.

“Every game has been do or die for us,” Arena said, overstating the predicament a bit. “Having our group together for a long period of time in 2017 [five separate camps] makes it easier to prepare. We understand each other. The [current] week is a lot smoother than it may have been in March.”

Arena summoned 26 players, all of whom were in at least one camp this year. Injuries cost him two probable starters (center back John Brooks and right back DeAndre Yedlin), but the core of the program is in place, featuring Howard, Bradley, Christian Pulisic and Clint Dempsey.

“We have a group of guys who are excited, who realize that the path last year has made us stronger and better,” Bradley said. “And now it’s on us to make sure that we can finish the job and allow ourselves the chance to look forward to playing at the World Cup next summer.”

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United States vs. Costa Rica

Where: Red Bull Arena in Harrison, N.J.

When: 6:55 p.m. Friday.

TV: ESPN, Univision.

CONCACAF standings

Mexico 4-0-2, 14 points

Costa Rica 3-1-2, 11

United States 2-2-2 8

Panama 1-1-4, 7

Honduras 1-3-2, 5

Trinidad & Tobago 1-5-0, 3

Other matches: Honduras at T&T, 8 p.m.; Panama at Mexico, 9:30.

Each team will play 10 games. Three will earn automatic berths. One will enter a playoff vs. Asia’s fifth-place finisher.

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