Medabots (1999)

Blurb:
Medabots, one of the hit shows on the Fox Kids Network, follows the adventures of ten-year-old Ikki, who knows everything about Medabots and Robattles but doesn’t have his own Medabot — until Metabee comes along. Ikki must contend not only with Metabee’s sometimes unpredictable behavior but also with two gangs, the Screws, Ikki’s schoolmates, and the criminal Rubberobos, who want Metabee for their own nefarious purposes. Can Metabee help Ikki foil the thieves trying to steal his Rare Medal?

Source: www.anisearch.com/manga/4749