To defend myself from I BJJ guy I have a very effective technique. Before he grabs you make a turn so your back is towards him. Then put your left foot before your right, now put your right foot before your left, repeat very fast.... run, just, run!
Again, just because they're a BJJ player doesn't make them immortal, or unbeatable. On the contrary, the best fighters in the world today (Silva, Weidman, Emiliananko, Jones) are all lights-out strikers. Quite frankly, the BJJ code has been cracked from some time now. Also, from a purely tactical standpoint, NEVER give up your back to a BJJ player, or anyone else for that matter. Better to stand your ground.
"One day as a lion is worth a lifetime as a lamb."