Given the distance between the two men, and the height advantage possessed by David, he had little worry that the kick was actually intended for his head. The other man would have to completely give up his balance and commit entirely to the attack, and even then the odds of reaching his head were not good thanks to the positioning of his back foot. So when the kick instead came in at his stomach, he twisted his torso to catch it on his right side (also cutting its journey off prematurely and thus limiting the power behind it) and wrapped his right arm around the extended limb, trapping it against his body. From there, he moved forward rapidly, left hand still held in a guard position, and attempted to push Dylan off balance and onto the ground. 

If successful, he would then use his new-found leverage to get on top of Dylan and begin driving punch after punch at the other man, alternating the powerful blows between his head and ribs.