Dorabase: Super Baseball Gaiden is a spinoff manga by Shintaro Mugiwara
Dorabase (ドラベース, Dorabesu) (subtitled Doraemon Super Baseball Gaiden (ドラえもん超野球(スーパーベースボール)外伝) is a baseball manga series by Shintaro Mugiwara based on the characters of long-running series Doraemon. It is published in Shogakukan's CoroCoro Comic magazine.
This comic follows the story of other robotic cats that form a baseball club. Though it shows Doraemon in the beginning, it doesn't focus on Doraemon itself (because Doraemon must go back to the past to help Nobita). It features a lot of imaginary ability, and in the baseball game, is allowed to use up to 3 gadgets. It has been published since 2002. The main character is Kuroemon, a robot cat like Doraemon, except he has ears and has black fur.