Sushi in Rio may seem random but there are two good reasons to try it. One, you'll probably tire of rice and beans. Two, Brazil has the largest population of Japanese outside of Japan so there are some excellent restaurants to choose from. Two modern, trendy venues on the same street are Manekineko and Sushi Leblon.
Manekineko: 021 2540 7461. Sushi Leblon: 021 2274 1342. Both on Rua Dias Ferreira, Leblon.