Visible crew/equipment: When Roy and Johnny leave Rampart and are heading back in the squad, about 16:40 minutes in, as they are discussing whether Roy has told his wife about house hunting, you can see two signs on the ceiling of the squad's cab. The signs say 'Emergency Saturday 8PM Rehearsal Mark VI Prod'. Possibly they are magnetic signs for the squad doors so people don't mistake the squad for a real fire department vehicle? (00:16:20)
Visible crew/equipment: While Roy and Johnny are climbing up to rescue the boy on the bridge, there's a closeup of the boy as he breathes heavily. When this shot pans to the right we see Roy (his stunt double actually) place the rope behind his back, and a mysterious dark gloved hand quickly appears behind Roy (and it's not Johnny's hand).
Visible crew/equipment: When Gage and DeSoto are driving away from Rampart, discussing DeSoto's possible purchase of a new house, dispatch calls about a traffic accident. In this exterior closeup shot of Squad 51, the reflection of the camera's flatbed vehicle is visible on Squad 51's red surface.
Visible crew/equipment: After Roy and Johnny speak to Chet's friend the realtor, when Station 51 is being dispatched to the accident on Harbor Freeway, in the overhead shot of the apparatus bay, we can see the shadow/reflection of production equipment moving on the engine's windshield.
Visible crew/equipment: When Station 51 is dispatched to the rescue on Johnson Canyon Bridge, just as Engine 51 rolls out of the apparatus bay, the reflection of array lighting and two reflector screens are visible on the engine.
Answer: I was rewatching a few first season episodes of Charlie's Angels (1976), and in S1xE6 "The Killing Kind," I recognized the same actor. So, to finally fully answer your question, the two baseball players in School Days are played by Rod Perry and Sean Fallon Walsh.
Super Grover ★