EAT YOUR VEGETABLES AND DON'T IGNORE YOUR TAKEDOWN DEFENSE: A SINGLE LEG COUNTER TO KIMURA.
Over the years, BJJ has made incredible gains, but, it's not without a few losses. Big gains I could spend all day describing. Losses? Well, the primary one is a lack of emphasis on takedown and takedown defense skills (the use of wrestling and judo). Most major competitions in modern day BJJ involve a lot pulling guard and "Aoki style" butt scooting. We could blame that on the point system in the IBJJF rules, but I prefer to blame the terrorists.
So, let's talk takedowns. In the rare case that someone attempts a single leg on you in BJJ, you can can make them pay dearly for it. Check out this submission counter to the single leg and make sure your partner never tries to take you down again.