When you go through the locker rooms and showers at the start of the Athletic Sector, you'll come to a short hall with two doors. One of the doors gets jammed, but the other opens up into the Basketball Court. In the center of the court is the first Rumbler that you'll encounter. As if this fight wasn't tough enough, when you enter the main lights go out, leaving the room very dim. Also, the floor has several Worm Piles on it that blend with its colour even with the lights on. If you're fast enough, you may run past the Rumbler to the Grav Lifts, or use the Photonic Redirection Psi Power to sneak past it. The Transmitter array is on the top floor above the Basketball court, but it is guarded by a pair of Cyborg Assassins. Take them out - after that you can just pick off the Rumbler with ranged weapons from above.
Alternatively, you can crouch into a small ventilation shaft on the right wall before the Rumbler catches up to you. The shaft leads to a swimming pool, though along the way and at its exit are a couple of Grub Eggs. Behind the pool there's a Recharge Station and Basketball Court lights' auxiliary power override that needs a charged Power Cell.
- You can trigger an Easter Egg in the Basketball Court by hitting the backboard with the Basketball taken from the Earth. System Shock 2 doesn't really have a throwing interface per se, but it can be done e.g. by dropping the Basketball from the balcony above. When you successfully hit the backboard, you receive a special Mail from an unexpected ally.