Keisuke Honda scored the only goal of the game to send Japan second of the group, behind leaders Holland who beat Denmark 2-0.

Cameroon boss Paul le Guen made several changes to the side which mostly represented the Lions in the 2010 African Cup of Nations.

Souleymanou Hamidou was preferred to Carlos Kameni in goal, whereas youngsters Joel Matip, Maxim Choupo-Moting and Nicolas N'Koulou were handed starting roles, along with Sebastian Bassong and Benoit Assou-Ekotto.

The first half was utterly a bore affair until late before the break, when Japan snatched the only goal of the game.

Cameroon's Eyong Enoh made the first attempt on target as late as the 38th minute, but goalkeeper Eiji Kawashima was equal to the low shot.

Seconds later, Japan were in front when Daisuke Matsui sent in an cross that was controlled by Honda, who fired home from point-blank range.

Insipid

Cameroon made a courageous start to the second half when star man Samuel Eto'o showed the first sign of his presence with a terrific piece of skill.

The Inter Milan ace bamboozled three Japanese defenders before setting up Choupo-Moting with a fine layoff, but the latter blasted wide.

The shy attempt was followed by little action from the insipid Cameroon, who struggled to penetrate the tight Japanese defense.

Le Guen brought in experienced trio Geremi, Achille Emana and Mohamadou Idrissou in an attempt to rejuvenate the quiet Eto'o, but to no avail.

The Lions' best chance of the game came four minutes from time when Stephane Mbia rattled the crossbar with a scorching effort from range.

But that was all Cameroon could do as Japan got the three points.