Barcelona on Tuesday ended a brief break in Japan before their Club World Cup battle by meeting children evacuated from the region around the crippled Fukushima nuclear power plant.
Lionel Messi, Xavi and other stars presented Barcelona shirts to 11 Fukushima children before an evening training session at a football park owned by the J-League Yokohama Marinos.
They also paused for a group picture before the players got onto the pitch to practice ahead of the European champions' semi-final clash with Asian champions Al Sadd of Qatar in Yokohama on Thursday.
"I'm very happy. I cannot wash my hands after I shook hands with Messi," 17-year-old Hikari Niitsuma told reporters after he was handed a shirt by the Argentine superstar.
Central defender Gerard Pique said: "It was great that we could meet them. I'd be happy if they enjoy watching our training session as well as the shirts with our names on them."
Barcelona arrived in Tokyo late Saturday, 14 hours after their 3-1 El Clasico victory away over Real Madrid.
Coach Pep Guardiola had given free time to his jet-lagged men for rest and relaxation after a brief midday training session on Monday. He said his men would go sightseeing in Tokyo and "eat a variety of genuine Japanese dishes".
Tens of thousands of people were evacuated from their homes after a massive earthquake and tsunami triggered a nuclear crisis at the Fukushima Daiichi nuclear plant in March, and are still uncertain when they may be able to return.