Your combo 3 is "side door entering" that you use your opponent's leading arm to jam his own back arm. You don't have to worry about your opponent's left arm that much.
Is there any reason that you let your opponent to punch you first? Do you have any combos that you punch your opponent first?
When you respond to your opponent's attack, you may fall into his trap. Will it be better to let your opponent to fall into your trap instead?
In this video, Bruce Lee uses right punch to bait for his opponent's left arm blocking. He then guides his opponent's left arm to jam his opponent's own right arm (his opponent falls into his trap). This way, when Bruce throws his back fist, his opponent has no arm to block it.
What if your opponent's punch just tries to bait your blocking arm like Bruce Lee did in his video?
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