The Germany football team came up with a cryptic message on Sunday in their latest protest aimed at 2022 World Cup hosts Qatar.
The Germans joined Denmark, Norway and the Netherlands in a growing movement in support of workers involved in building World Cup venues in the Gulf state.
Human rights groups have been heavily critical of the treatment of migrant workers, claims Qatar disputes.
Before their 1-0 win over Romania in Bucharest on Sunday, the German team briefly reversed their shirts prior to kick-off with the numbers facing forwards.
The subtle gesture was intended to draw attention to the United Nations' 30-point declaration of Human Rights.
The German FA account posted "We are 30!" over a picture of the team on Twitter with each players' number referring to one of the articles.
"We all stand for fair play, not only on the pitch but also off it," said Germany captain Manuel Neuer.
"We stand for these 30 human rights articles, for diversity and against discrimination.
"That's what we wanted to show.
"The idea came from the team again, as it did before the match against Iceland," added Neuer.
Last Thursday, the German team wore T-shirts which spelt out "Human Rights" before their 3-0 win over Iceland in their opening qualifier.
The German Football Association (DFB) has supported the national team's protests.
"Every single sign is powerful and effective," said DFB president Fritz Keller in a statement on their website.
"But of course we must and will continue to raise our voices.
"We play for people and not for governments."
However, Keller implied the German FA is against boycotting the 2022 finals.
"We are in contact with... experts from non-governmental organisations," he added.
"Amnesty International advises against a boycott and rather demands dialogue with those involved, setting clear signals - as the national team did" by wearing the T-shirts which spelt "Human Rights".
Germany midfielder Joshua Kimmich has said talk of a boycott is "10 years too late".
"We should have thought about it at the time," he added, referring to the World Cup finals being awarded to Qatar back in 2010.
Elsewhere, Danish players wore shirts with "Football supports CHANGE" before their qualifier against Moldova on Sunday.
Norway also wore t-shirts stating "Human rights, on and off the pitch" prior to recent games against Gibraltar and Turkey.
The Dutch team also wore T-shirts with the message "Football supports CHANGE" before their 1-0 win over Latvia in Amsterdam on Saturday.