CUIABA, June 21: The bomb attack that killed at least 21 people watching a World Cup game in Nigeria has cast a sombre shadow over the African champions’ build-up to Saturday’s date with Bosnia-Hercegovina in Cuiaba.

Tuesday night’s bomb exploded in the midst of a crowd watching Brazil play Mexico on a giant screen in Damataru, capital of Yobe state.

Stephan Keshi’s men observed one minute’s silence at training on Wednesday as team media officer Ben Alaiya predicted the atrocity would add further motivation for a strong performance at the Arena Pantanal.

Not that any extra incentive is needed as a win would push them onto four points and in a solid enough position to secure a ticket to the knockout stages as runners-up to likely table toppers Argentina.

They will have a clearer idea of what’s required before kick-off with Iran tackling Argentina earlier in the day.

Nigeria stand on one point, the reward for their part in the much-maligned goalless stalemate with Iran which left them without a World Cup win in nine matches.

One certitude about Saturday’s game is that defeat for Bosnia would mean an early trip back to Sarajevo after their concluding first round fixture, against Iran, next week.

Bosnia were stumped by Lionel Messi who set up the opening goal and then conjured up a superb second in Argentina’s 2-1 win.

Coach Safet Susic has vowed that his men will step up a gear after a tactical move not to go all out against the South American giants.

“It was not a key match. We could afford to lose so long as it wasn’t a thrashing,” said the former world class attacking midfielder for Paris Saint-Germain and the former Yugoslavia.

“That is what we did. I hope that Argentina will win their other two games, because if they do then the second place spot will be between Iran, Nigeria and Bosnia.”

He intends shaking things up in attack, with Vedad Ibisevic, scorer of Bosnia’s goal in the first game, joining Eden Dzeko for the remaining two group matches.

“We couldn’t afford to play with two strikers against Argentina, who have so many attacking midfielders,” Susic explained.

Keshi meanwhile will be anxious to see his Super Eagles take flight in Brazil at the second attempt, not least to prove former captain Jay-Jay Okocha’s criticism of him after the Iranian game was unfounded.

“This was a must-win for Nigeria but we did not take it,” Okocha, who netted 14 times during a 13-year international career, railed.

“We did not do enough in terms of our tactical play. Keshi did not do enough work on the team. The tactical play of Eagles was so bad, I hold Keshi responsible for this.”

The man himself countered: “Just because we didn’t win people think we played badly. I don’t think we played badly, it was just that we didn’t score the goals we needed.”

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