First off, are we talking ju-jitsu or the Brazilian type?
Either way, he's gonna try and get you on the ground or at least close to you to apply a lock or choke hold, so ask a friend who wrestles to teach you how to "sprawl" if the guy goes for your legs. Of course, in a street fight, you don't just kick your feet back, lower your hips, and push the guy's head down (like you wd on the mat), but also come underneath with your free hand and chop him across the throat or hammerfist him on the back of the head or the base of the neck (it'll serve the chump right for idiotically exposing his spine or the back of his head to an opponent). Learn the sprawl just in case.
However, what you wanna do is to avoid putting yourself in a position for the other guy to go for your legs or try to flip you to the ground, so keep circling him, first one way and the other, and show him a lot of head, hand, and foot fakes, which will be particularly effective after you've landed more than a few jabs. And, that's the other thing: unless you get the chump out of position to defend himself, stick to using the "stick" i.e. the jab - your jab may not hurt the guy, but you can cut him up with it, split his lip, close an eye or two, etc. Another good thing about the jab is that you don't leave yourself as open to counterpunches as you do with "powerpunches" (assuming you keep your chin tucked down, keep your right glove up, AND circle to the right or left when throwing the jab or, better yet, ALWAYS throwing multiple jabs while rolling right or left).
Last bit of advice, make him come to you and initiate the action: being the guy who "lays back" gives you more options and it's easier to counterpunch than lead. Good luck.
Jiu Jitsu is for the ground, so keep it standing. Keep your distance by using HARD jabs and don't get too close to him. The further you are, the less your instinct timing matters. Keep using the jabs, don't rush into him, keep your distance and use your HEAD to think and whoop the man's butt. Use distance and footwork, those two are your bestfriends next to the jab. When he comes to take you down, jump back and throw a hook. Keep off the ground if he is trained in there. Most Jiu Jitsu guys aren't good at stand up and that's why they take the ground game. Just come in confident and make him scared to fight you standing. Throw punches and put him in the defense.
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First of all, there's no justifiable reason for you to fight your ex's current boyfriend. Remember that we should only fight for the right reasons, and the only right reason is self-defense. We shouldn't fight for petty things such as envy or jealousy. Secondly, if you don't even have formal or proper training for fighting, well, just forget it. Prudence is the better part of valor. You might just get seriously hurt.
You say he's trained .. Does he do that as a sport or something?
If so, he's not allowed to fight because that's only for self Defence or sport not to initiate fights.. He can go to jail for that, or can just get in some serious trouble
My ex girlfriend's current boyfriend who does jui-jitsu wants to fight me. I need help because I can fight, but this kid is trained to fight, any tips??
