Gordon Strachan has praised the determination of the USA to succeed ahead of Friday night's Vauxhall International Challenge match against Scotland at Hampden Park.
Soccer still struggles to get the attention and profile of the more traditional sports in the United States - American Football, basketball and baseball - but it continues to go from strength to strength.
Jurgen Klinsmann has taken the US side to 13th place in the FIFA rankings and they will take part in their seventh consecutive World Cup finals next summer in Brazil while the Scots, having failed to make it to the finals, are looking further ahead to the start of the Euro 2016 qualifiers which are the best part of a year away.
"When they put their minds to something they can do it well," said the Scotland manager, who has promised not to turn the match into "a farce" by making too many substitutions.
"If you look at the nation as a whole, in sports, they have great athletes.
"They have brought that athletic style to their football, with no lack of ability.
"They have improved tremendously. It has been great at grass roots for the last 40 years but because their players are getting about in Europe and the rest of the world, it has improved them all-round as players."
Klinsmann admits he is "sad" that the Scots will not be joining the USA in Brazil.
"It is sad to see that Scotland didn't qualify because everybody wants to see Scotland in the World Cup, also because of their fantastic fans," he said.
"They are known world wide. When you think of Scottish football, you think of the passion and players dedicated to the team with work rate and individual talent.
"They are always emotional, they give you everything they have, so this game is a good benchmark."
The former Germany manager will read nothing into the 5-1 win over Scotland in their post-season friendly match in Jacksonville in 2012.
"It is a completely different game and we are well aware of that," he said.
"Scotland did us a favour coming over after their season was over, in 95 degrees, and we knew it was going to be very difficult for us.
"We were on a totally different page then. We know that Scotland in any given moment, can score and can beat us.
"So we are going to be very alert."