I dug out the old photos of the Main Street Gym and fired up the scanner at the Daily Mirror HQ.
Photograph by Marilynn K. Yee / Los Angeles Times
Then I took a closer look at this picture from 1976.
Hm. What’s this?
And what’s this?
Why that looks like an old theater.
Hm. Look at this architectural detail.
The Main Street Gym was at 318 1/2 S. Main St. What theater would have been next door at 320 S. Main St.?
Aha, it’s our old pal the Hippodrome!
But the Hippodrome was supposedly torn down in 1952 for a parking lot. I started wondering if the facade was saved for offices.
Then I noticed this about the interior of the Main Street Gym in another 1976 photo:
Photograph by Marilynn K. Yee / Los Angeles Times
What’s in the background? It looks like a small proscenium.
Here’s a detail.
Look at the light sockets in the archway.
I wonder if the Main Street Gym was in some upstairs dance hall at what used to be the Hippodrome. If anyone can shed light on this little mystery, let me know…
ladailymirror.com 
The auditorium of the theater was torn down in the early 50s. The facade and upstairs space was preserved. The upstairs was the gym, obviously. Parking was in the lot behind the facade. The whole thing was torn down in 1984.
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Can anyone shed ligh on who the two guys are that are sparring, am I correct to believe one of them is Monroe Brooks who fought Roberto Duran and Bruce curry?
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I know the trainer standing on the right side boxing ring top corner his name is Pat Mc~Guire I sparred over a thousand round’s ther @ the Main Street Gym ” with champ’s like Danny “Lil Red ” Lopez , Sean Ogrady , Esteban De Jesus, Vilamar Fernandez, Bobby ” School Boy ” Chacon, Ray “Boom Boom” Mancini, also many contender’s, it was the gym to go and find the best fighter’s in the world .
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Not sure if you will get this but, my grandfather ran the main st. gym in the 50’s , I have a lot of old pic of him and my uncle in the gym. and the Fighters he work with.
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