Ah, but sir, you're still able to capture a pokemon after it's knocked out. I've done it before. Don't worry though, I have just the idea for this.

[ The Shuppet uses spite. It screeches with an ear-wrecking high octave. ] Sneasel! Beat up! [ Sneasel flashes his way to it before smashing it in the face and grabbing its body to toss down on the ground. ]

If you wished to toss a ball at it, now would be the right time. [ However, Sneasel is grappling it in a way where if one's aim isn't exceptional, it'll hit him and not Shuppet instead. ]