From the Super Mario Wiki
Sluggers are yellow Bandits that hold baseball bats around the time of Super Mario World 2: Yoshi's Island, the remake, Yoshi's Island: Super Mario Advance 3 and the sequel, Yoshi's Island DS. They use teamwork with their green-colored counterparts, Green Gloves. If a Yoshi throws an Yoshi Egg toward one, the Sluggers will hit it back with the bat. Although it won't hurt them, it might push them. If a Yoshi throws a Chomp Rock at them, they will hit it back at Yoshi.
Sluggers are immune to a Yoshi's tongue, so they can't be eaten, however, Ground Pounding their heads or stepping on them repeatedly will defeat them. They can be used to reach items like Flowers that are out of reach by ricocheting an egg off a wall.
Sluggers are part of the Baseball Boys.
Names in other languages
|Roughly "young Mr. Bat"; 「くん」 kun is a title used to refer to (usually male) children/teenagers, and 「バット」 batto means "bat".
||From "schlagen" (to bat) and "Jason", the original German name of the Bandits