It may be time-consuming to get this achievement, but it's really not as difficult as it may seem.
First of all, get a friend and start a 1v1 ranked match roughly at the same time with them. I've done it with a friend who was in a nearby region, but we sometimes matched on "Same Region" and most of the time we matched on "Worldwide" so it can be pretty random. I also recommend playing at a time where there's less people. It worked best for us at about 7-8PM GMT. We still encountered a few people though.
Lastly and most importantly, if you pair with someone other than your friend make sure to Alt+F4. Do this as soon as you see their name pop up on screen and you should be fine. Even if you get the option to decline the challenge, close the game with Alt+F4 because if you run into them again, it'll usually start the match instantly anyway.
Other than that, it just takes some luck and patience! On one of the attempts you should choose Bo' Rai Cho and win without getting a 4-hit combo (so just do uppercuts or something) to get the "Lands-Down" achievement.