Idk anymore, unless the chapter somehow explains logically what just happend, it's over.
Hajrudin punching Imu mid attack when he was Off guard and then sending him flying, isn't, even necesarily the issue, considering it was etablished Hajrudin had enough power sending 10.000 tons flying, before he grew even stronger, so it was etablished he has great physical strength.
But, how in the world does it make sense for him to somehow catch up to them and Interrupting Imu's attack at the exact right moment and then being capable of tanking Just 3 Omen shots nonchalantly with his back being turned to the attack, when back in Dressrosa, dude was knocked Out by single G2 Jet Pistol

