Yes

Taking a moment to think it over, Ash came to a conclusion.

"Okay. I'll be your partner." the trainer remarked, watching the rabbit pokemon perk up. "Just let me get a pokeball."

Ash pulled a pokeball out of his pocket. What followed, was him setting it right on Lopunny's nose.

"Lop."

Lopunny was sucked on in, the ball falling to the ground.

One shake.

Two shakes.

Three shakes.

A click. Ash picked up the ball, letting out his new partner.

"Anything else you wish to do?" he inquired, watching Lopunny bolt off to his mom's room.