These two familiar but fiercely bitter rivals are set to clash in Manama on Saturday, their third encounter this year alone, and the winner is expected to become a front-runner to win one of the top two spots in Group A and ensure a place in the finals, to be held in South Africa. Australia, Uzbekistan and Qatar are the other three teams in this group.
The top two go through to the finals while the third-placed team tackle their counterparts in Group B, with the winner of that playoff going on to face the Oceania zone winners for a spot in the finals.
Japan, the three-time AFC Asian Cup champions and three-time appearants at the FIFA World Cup, may hold a clear edge in terms of experience, enterprise and exposure, but Bahrain has come a long way since the turn of the new millennium.
The tiny Gulf kingdom is no more a minnow, and the Japanese themselves found this out the hard way when they lost 1-0 to Bahrain in the third qualifying round five months ago.
That victory not only helped Bahrain break a jinx, but also enabled youngsters in the side to find new levels of confidence. The seniors, particularly talismanic striker Ala'a Hubail who scored the match-winner, rediscovered themselves at the right time.
Japan did avenge that defeat in the return match by the same margin, but it was a soft victory as by then both sides had already booked their places in the fourth and final round of qualifiers.
The heat, both on and off the field, is certainly intense in the desert kingdom, and the Japanese coach Takeshi Okada is already feeling it. "I knew it would be this hot. I hope my squad will get used to it," said Okada.
The Bahrainis, however, will be more at home as the summer has already peaked and the temperature has begun to drop. A late night kick-off (9.30 p.m. local time) due to fasting during the holy month of Ramadan may also work to the hosts' advantage.
But wily Bahrain coach Milan Macala is not prepared to discuss the weather or any other external factors. The 64-year-old's focus is purely on winning all three points. "We are 100 per cent positive and are aiming for victory," he said. "This will be my seventh match against them. It will be a tough one, but we are very well prepared for it."
Bahrain played two friendly matches against Burkina Faso and the UAE and won both, 3-1 and 3-2 respectively, as part of a build up to Saturday's crunch clash.
Japan has had an equally tough build up. Moreover, Okada has named a strong squad including four Europe-based players - the charismatic Shunsuke Nakamura (Celtic), Junichi Inamoto (Eintracht Frankfurt), Daisuke Matsui (Saint Etienne) and Makoto Hasebe (Vfl Wolfsburg).
The only spot of worry for the visitors is Nakamura's right ankle, which was sprained in an early qualifier in June. But coach Okada is confident that his star player will be fully fit for the match. Bahrain are also at full strength with all their overseas players, including prolific scorer Salman Isa, in the ranks.
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