Scotland slipped a second friendly defeat of this international break, losing 1-0 to Ivory Coast in Liverpool.
Following Saturday's home defeat to Japan, Scotland offered more intent and endeavour with their performance but were found wanting in both boxes.
It was another flat display at Everton's Hill Dickinson Stadium, watched by Sir Alex Ferguson, Sir Kenny Dalglish and Toffees boss David Moyes. Like at Hampden Park, there were a smattering of boos at half-time and full-time for Steve Clarke's men.
Clarke made nine changes, handing opportunities to some fringe players to make their mark in a 3-5-2 formation which allowed him to play two strikers in George Hirst and Che Adams.
Only captain Andy Robertson - winning his 92nd cap to put him only 10 behind the all-time appearance leader Dalglish - and Scott McTominay kept their places.
However, former Arsenal man Nicolas Pepe bundled Ivory Coast in front on 12 minutes and Scotland couldn't find the required quality or inspiration to get on the scoresheet.
Falkirk goalkeeper Scott Bain and Bologna midfielder Lewis Ferguson came on for the second half in which Scotland stepped up the pressure but still struggled to create clear-cut chances.
Hirst twice fired over from the edge of the area but they remained vulnerable on the counter.
Substitute Nathan Patterson's well-timed tackle in the penalty area prevented Amad Diallo pulling the trigger after a break from a Scotland corner while Bain pulled off a good save to deny the Manchester United winger, before Simon Adingra hit the post in added-time.
Scotland have two more warm-up games against Curacao and an as-yet-unnamed opponent before they take to the biggest stage of all for the first time in 28 years in the USA, where they face Haiti, Morocco and Brazil in their group.
Scotland boss Steve Clarke said:
"The more you speak about it [the boos] the more you encourage people to be negative. I thought my team were very positive.
"I don't think we deserved to lose. We started well, looking bright and trying to get forward. Our system caused them a problem to start with but we allowed a really poor goal from a counter attack. Really good teams punish that. They're a good team.
"Our reaction wasn't good. We lost control of the game. That is something we have to be better at.
"In the second half we dominated the game. We didn't create anything clean but that is credit to Ivory Coast.
"We need quality and calmness in the final third. If you do that, chances will come."
Scotland captain Andy Robertson speaking to BBC Scotland:
"Second half we really got to grips with where we needed to be off the ball and I thought we caused them problems.
"Obviously they were 1-0 up but we were the team pushing forward and trying to create.
"It's a friendly. We want to win these games, of course we do, but we're also trying stuff and you see that with the changes we made.
"A lot to learn but some really good signs, especially in the second half."
