Nigeria's footballers say a bomb attack that killed at least 21 people watching a World Cup game in their country gives them added determination to do well in Brazil.
The bomb exploded in the midst of a crowd watching Brazil play Mexico on a giant screen in Damataru, capital of Yobe state, on Tuesday night.
Nigeria's players held a minute's silence before they started training under the floodlights in Campinas, outside Sao Paulo, on Wednesday.
"It's unfortunate, especially as it concerns football," said team media officer Ben Alaiya of the attack.
"It further boosts the determination of the players to do well against Bosnia and win for them because it's the love of football that led to so many people dying, while they were watching the game. It's sad that it happened."
Nigeria play their next Group F game against Bosnia in Cuiaba on Saturday (Sunday AEST).
Nearly all of the Nigerian squad play in European and other foreign teams. But Alaiya said football is a unifying force in the West African nation.
"We want to win, want to do well for those lives that were lost and for the Nigerian people who have seen football as a force to bring them together all the times," added the spokesman.
"It's shocking that some people could engage in such callous acts against their fellow human beings at a time that the world is in celebration mood for the biggest sport in the world.
"Our heart goes out to them. We feel very pained and we want to win for them. Even if we win the trophy it will not bring back lives that were lost."
At least 21 people were killed in the football bomb attack, according to a medical source, although state police put the death toll 14. Nigeria's police advised fans to stay away from public venues showing matches.
Previous deadly attacks on big screen venues in Nigeria blamed on Boko Haram militants have prompted at least two states to close such centres on security grounds.
Nigeria, who won last year's Africa Cup of Nations, started their World Cup campaign with a turgid 0-0 draw against Iran in Curitiba.
The Super Eagles have played in five of the past six World Cups. But after reaching the second round in 1994 and 1998, have taken just two points from their past six matches in the finals.