Steve Clarke expressed surprise and disappointment after being booed by the Tartan Army after Scotland lost 1-0 to Japan at Hampden Park.
Scotland received cheers off the pitch after qualifying for the World Cup finals for the first time since 1998 with a dramatic 4-2 win over Denmark in November.
However, their appearance was more calm as they returned to the National Stadium for their first warm-up game in North America.
Japan’s Junya Ito celebrates scoring the winning goal against Scotland.
Both teams hit the goalpost in the first half, but in the 84th minute, Hajime Moriyasu’s away team attempted a breakthrough by bringing in substitute Junya Ito, and the home fans expressed their disappointment in the second half.
Asked if he was surprised by the fans’ reaction, Clark said: “Yes, I was disappointed, to be honest.
“It’s the modern way. Nowadays, if you lose a game, you get booed.
“You have to deal with it. It disappoints me.”
Scotland face Ivory Coast at Everton’s Hill Dickinson Stadium on Tuesday night. They have two more warm-up games against Curacao and yet-to-be-named opponents before heading to the United States on their biggest stage for the first time in 28 years to face Haiti, Morocco and Brazil in the group stages.
If there was an anti-climactic atmosphere in the match against Japan, there is no doubt that the Tartans will see a more energetic home side at key moments this summer.
Middlesbrough striker Tommy Conway earned his first start, while skipper Andy Robertson earned his 91st cap, taking him into second place alongside former Aberdeen and Manchester United goalkeeper Jim Leighton.
Japan national team captain Daizen Maeda was the most familiar face to home fans.
The visitors, who are reaching their eighth successive World Cup final, survived an early scare.
In the 8th minute, Scott McTominay had a chance to open the scoring when fellow midfielder John McGinn crossed from the right, but his unconvincing shot from 10 yards was pushed into the net and safe by Japan goalkeeper Shion Suzuki.
Scott McTominay came closest to Scotland.
Moments later at the other end, Joel Fujita had the time and space to send in a powerful drive from 30 yards, testing Gunn and denying Kodai Sano’s long-range effort just before the half-hour mark.
The home side defended a series of corner kicks as Japan held the ball tight, and in the 38th minute Sano hit the top of the bar with a side-footed drive from inside the box. The game went back and forth.
Gunn thwarted Yuito Suzuki before Japan’s goal, McTominay’s header was blocked by Suzuki and the Napoli playmaker saw his free-kick from 25 yards tipped over the bar by the Parma keeper early in the second half.
Suzuki blocked Robertson’s drive past the post as Scotland picked up the pace.
Kaoru Mitoma, one of Japan’s many substitutes for Ryan Christie and George Hirst for McGinn and Lyndon Dykes, fired a shot from the edge of the box after a corner had been cleared, with Gunn denying Ito moments later.
The visitors’ threat increased and Scotland midfielder Kenny McLean blocked Ito’s dunk in the 69th minute before Hurst hit the side netting with a drive.
Findlay Curtis made his debut in the 80th minute, replacing Conway, but four minutes later Genk midfielder Ito burst into the Scotland box and beat Gunn from 12 yards to end the deadlock.
Ito dismisses Japan’s late winner
‘A little lesson’ for Clark
The Granite City head coach Steve Clark:
“You have to look at the level of the opposition. We are playing against a top-level team and eventually they are bringing in stronger and stronger players.
“We had a player on the pitch who needed minutes, but we needed to protect him towards the end of the game, so we took the opposite approach.
“It’s about continuing to work, continuing to do what we do.
“I didn’t expect it to be a low-scoring game. Even the goals we conceded came from poor choices, going forward too early and lack of organization after defending set plays.
“We can take small lessons, but I think it shows that if you make bad decisions against a top team, you will be punished.
“It was disappointing to lose the game. To be honest, I don’t think it was a game we should have lost.
“I’ll go and analyze the film. One or two things I thought were good about the game, I thought we defended pretty well, I thought our two centre-backs were good, I thought Angus scored a really good goal.”
