Despite not having the Reverse De La Riva Guard as a part of his normal game, Marcelo walks Dillon through a way to transition from the Reverse DLR to Single-Leg X (or at the very least, Shin-to-Shin Single-Leg Control). Use your foot to push his weight away enough to extend his leg, clearing the space for you to sit up, go shin to shin, and hug the knee. Expect your opponent to drive back into you, so meet his pressure with a stiff arm to keep the space. Also, prepare for his more than likely back-step by fishing his leg with a hook before or as he tries.