Our Instructors

– First Class Free
– Our instructors have fun and teach solid


Core Values

Our professional black belt has been training for many years and is an expert in the practice. Our team is committed to provide excellent training to our students.

  1. Teach and produce great jiu jitsu
  2. Have as much fun as possible doing it
  3. Leave your troubles at the door and train
  4. Commitment to excellence in all you do

Our Instructors

Professor Brenton Fitzgerald, Owner and Head Instructor, 3rd Degree Black Belt, Ironman Finisher

Professor Brenton FitzgeraldBrenton has been practicing Brazilian Jiu Jitsu since 2002. Before that, he was an accomplished wrestler starting at the young age of 9, in 1986. He started under Professor Henry Matamoros and earned the rank of brown belt under Professor Matamoros.

After over 5 years at the rank of brown belt, on May 17th, 2015, Professor Matamoros instructor Master Pedro Sauer promoted Brenton to Black Belt. Master Sauer received his Black Belt from Grand Master Helio Gracie who is considered to be the founder of Brazilian Jiu Jitsu.

That means Brenton is 2 degrees of separation from the foundation of the art. He has trained with Professor Jon Freidland (also a Master Sauer Black Belt) at Neutral Ground for the past years and is excited to carry on the tradition of great Jiu Jitsu under the banner of Fluid Jiu Jitsu.

My Story
I was a very good wrestler. At age 24 and my career behind me, I challenged anyone and everyone to wrestling matches. My sister was dating a man named Mike Contreras. He accepted my offer. I took him down, I held him on his back for 3-4 minutes. This was well more than enough to win a wrestling match, it did not win the fight. I could not make him quit. After a few minutes, I got tired and Mike effortlessly lifted me off of him (he was 20lbs lighter than me) and turned me 90 degrees in midair, set me down very gently and applied an arm bar. I had to tap out and give up so he would not break my arm. I asked how he did that and he said Brazilian Jiu Jitsu! I had been a wrestler for 15 years, Mike had been in Jiu Jitsu for 2 years and never wrestled before.

I found Professor Henry Matamoros two weeks later and have not stopped training since. I never wanted to be beaten that bad ever again. I have been beaten since. That is part of being humbled by this art, but I also want to show the average person how to beat a good wrestler with the great technique just like I was beaten.

I finished Ironman Chattanooga 2017. This race consisted of a 2.4 mile swim, a 116 mile bike ride and a 26.2 mile run. This is one of the greatest accomplishments of my life. I estimate I am one of maybe 1-15 people in the world to earn a BJJ black belt and finish an Ironman in the world. There are around 10,000 BJJ black belts and around 500,000 Ironman finishers.

Mike Caughey, Brazilian Jiu Jitsu Instructor, 1st Degree Black Belt

Mike Caughey, Brazilian Jiu Jitsu Instructor, Black Belt

Mike has been involved with Jiu Jitsu since 2008. He holds the rank of black belt in both Brazilian Jiu Jitsu and Judo. His passion is to coach and guide others to be the best they can at the gentle art.

Jason Lippert, Brazilian Jiu Jitsu Instructor, Black Belt


Bio: 50-year old black belt under Prof. Pedro Sauer (Summer of 2020) after 14 years total training over the span of 23 years. Claim to fame: Lost matches to both Prof. Henry “The Don” Matamoros and Prof. Jeff “Big Frog” Curran when Henry was a white belt and Curran was a blue belt (?) at a tournament in Fond du Lac in ’97.

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Fluid Jiu Jitsu
4908 S. 74th St
Greenfield, WI 53220
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11:00 am - 1:30 pm, 5:30 pm - 9:30 pm
6:00 am - 7:30 am, 5:30 pm - 9:30 pm
4:00 pm - 9:30 pm
6:00 am - 7:30 am, 5:30 pm - 9:30 pm
11:00 am - 1:30 pm, 4:30 pm - 9:00 pm
9:30 am - 1:30 pm
10:30 am - 1:30 pm

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