Your friend cheated you. Beldum, Metagross's first stage, can only be obtained in a Pokeball, in Ruby/Saphire/or Emerald in a Pokeball on a desk much like Eevee in the old games, and it evolves to Metang at Lv. 20, then Metagross at 55. Yours says: met at a route in a DS game, caught in a master ball, and at Lv. 53.