Often times people with longer limbs will use their range and throw lazy punches, particularly a lazy jab. One over looked technique is beating their arms up as they punch also known as defanging the snake in arts like silat.
Fire uppercuts and hooks at their forearm as they strike. The blood will pool up in their forearm and the punches will become slower and slower. Also it is demoralizing.
Obviously closing the distance is another great option and keeping that distance closed.
Couch 2 Cage