pleased as punch

"to thrust, push; jostle;" also, "prod, to drive (cattle, etc.) by poking and prodding," late 14c., from Old French ponchonner "to punch, prick, stamp," from ponchon "pointed tool, piercing weapon" (see punch (n.1)). Meaning "to pierce, emboss with a tool" is from early 15c.; meaning "to stab, puncture" is from mid-15c. To punch a ticket, etc., is from mid-15c. To punch the clock "record one's arrival at or departure from the workplace using an automated timing device" is from 1900. Related: Punched; punching.

Specialized sense "to hit with the fist" first recorded 1520s. Cf. Latin pugnare "to fight with the fists," from a root meaning "to pierce, sting." In English this was probably influenced by punish; "punch" or "punsch" for "punish" is found in documents from 14c.-15c.:

To punch (someone) out "beat up" is from 1971.