Whether Jurgen Klinsmann keeps his job as coach of the United States men's national team in the wake of Tuesday's 4-0 loss in Costa Rica remains to be seen. But the U.S. Soccer Federation has been gauging the interest of potential replacements since at least late last year, multiple sources have told ESPN FC.

U.S. Soccer has been in contact with LA Galaxy boss Bruce Arena and Sporting Kansas City counterpart Peter Vermes within the past 12 months, the sources said. The federation declined to comment on Thursday.

After Tuesday's World Cup qualifier, The Washington Post reported that the USSF has been lining up Arena to replace Klinsmann.

Arena's contract with the Galaxy was set to expire next month, but the 65-year-old recently signed a two-year extension with the MLS club, multiple sources said. However, the new deal would allow Arena -- who coached the U.S. at the 2002 and 2006 World Cups -- to leave if he were offered the national team job.

Tab Ramos, Klinsmann's current assistant, could also be a candidate for the position if the manager is let go, one source said.

Klinsmann is under contract through 2018, but his future is in doubt after the Americans lost consecutive World Cup qualifiers in the past week. Before the heavy defeat in Costa Rica, the U.S. lost 2-1 to chief rival Mexico in Columbus, Ohio, on Nov. 11.

U.S. Soccer president Sunil Gulati said before the Mexico match that he expected Klinsmann to remain in place through qualifying for Russia 2018.

But Gulati sounded less certain after Tuesday's loss, telling reporters, "We'll think about what happened today and talk with Jurgen and look at the situation."

Jurgen Klinsmann's future is in jeopardy after defeats to Mexico and Costa Rica in the past week. Joe Maiorana-USA TODAY Sports

Multiple reports in Germany said Klinsmann was attending a state dinner in Berlin on Thursday during the visit of U.S. President Barack Obama.

Arena has been asked about replacing Klinsmann at various points during the German's turbulent five-year tenure and has usually declined to answer. Speaking to ESPN The Magazine in March 2013, Arena said, "I don't think it's right for a fellow professional to comment on somebody else's job."

But in an interview with Fox's Alexi Lalas in April of this year, Arena said he would consider coming back "under the right circumstances."

"I am not auditioning for the national team job, I'm not publicly advocating that Jurgen be relieved of his duties as the national team coach," he said. "If I was asked to become the national team coach again, I would certainly be interested in doing that."

Arena took the U.S. to the quarterfinals of the 2002 World Cup in South Korea and Japan, the team's best finish since the inaugural event in 1930, but Gulati fired him after the U.S. failed to advance to the knockout stage in 2006 in Germany.

The Brooklyn native has been the Galaxy's coach and general manager since 2008, leading them to three MLS Cup wins in his seven full seasons. He has won five MLS Cups, having led D.C. United to a pair of championships in the late 1990s before replacing Steve Sampson as U.S. coach in 1998.

Vermes, 49, led Sporting KC to the 2013 MLS title. He captained the national team at the 1990 World Cup, where he played alongside Ramos, a fellow New Jersey product.

In addition to his duties with the senior team, Ramos, 50, also serves as the U.S. under-20 coach.

Doug McIntyre (@DougMacESPN) is a staff writer for ESPN The Magazine and ESPN FC. Jeff Carlisle (@JeffreyCarlisle) covers MLS and the U.S. national team for ESPN FC.