It's How You Play the Game - S4-E19
Other mistake: After Chet says that he doesn't like when people expect too much of him, Squad 51 is dispatched to "man bit by an animal," and when Roy gets into the squad the highly reflective chrome spotlight has been sprayed with a dulling spray, to temporarily dull the surface.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Johnny walks into the kitchen and gets the cold shoulder from Marco and Mike, and then when Chet walks in, the reflection of production equipment is visible on the oven's glass.
It's How You Play the Game - S4-E19
Continuity mistake: When Squad 51 dispatched to 'man bitten by animal', the center chrome on lightbar is a solid piece, but en route the chrome center is striped and its trim is covered with black tape. Then when they approach the car lot, the black tape is gone.
It's How You Play the Game - S4-E19
Visible crew/equipment: After Mike and Marco ignore Johnny as he walks into the kitchen, when Roy holds the chrome coffee pot and pours Johnny a cup of coffee, the reflections of the camera/lights are visible on the coffee pot's chrome surface.
It's How You Play the Game - S4-E19
Audio problem: At the scene of the vehicle accident, Johnny asks the driver, "Where does it hurt?" but when he continues to ask, "Right here?" we can see he's not actually moving his mouth, just before he's punched in the nose by the driver.
It's How You Play the Game - S4-E19
Continuity mistake: When Johnny is in the ambulance with the car salesman that was bitten by the tiger, Johnny opens the man's shirt, but does not remove his western tie scarf. However, in the man's closeup the tie is open with the scarf slide removed, and then it's back to being tied with the slide.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Roy and Johnny are on scene at the car accident, the bulging outlines of their mic transmitters and wires are visible on the left sides (above the belts) of their shirts.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Johnny and Roy get the car salesman out of the car with the tiger, and when Johnny gets into the ambulance with him, the outline of the mic transmitter is visible at the side of Johnny's shirt.
It's How You Play the Game - S4-E19
Character mistake: On scene at the vehicle accident, John palpates a pulse on the driver's leg and tells Roy that he's got a good strong foot pulse. Then when Roy's on the line with Rampart we hear him say, "He has a strong fetal pulse," but presumably Roy certainly must have meant to say, "strong pedal pulse."
It's How You Play the Game - S4-E19
Continuity mistake: While Johnny tells the other guys that the losers of the baseball game, between 51 and 36, will have to pay for the entire cost of the picnic, Chet's eating an apple which has less eaten by the time he tosses it into the garbage.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Squad 51 is en route to the car salesman who was bitten by a tiger, just before the squad turns into the car lot, the reflection of the filming vehicle is visible in the squad's spotlight.
It's How You Play the Game - S4-E19
Visible crew/equipment: At the scene of the traffic accident, when the injured driver starts shouting just before they load the stretcher onto the ambulance, a ducking crew member's head dips into view at the bottom, right corner of the screen.
It's How You Play the Game - S4-E19
Visible crew/equipment: After John is punched in the nose at the scene of the traffic accident, when the ambulance arrives the reflection of set lighting is visible on the surface of the ambulance.
Revealing mistake: At the apartment complex fire, after Johnny is knocked unconscious by the explosion, when the Pasadena fireman finds him and has to lift him up, it's funny how even though Johnny's unconscious we can see that he actually helps to stand himself up, so the fireman can lift him up and carry him out.
Revealing mistake: At the apartment complex where the jet fighter had crashed there's an explosion, and when one of the firefighters becomes engulfed in flames his helmet falls off, and the special fireproof headpiece that the stuntman is wearing is visible.
Visible crew/equipment: Just after Herbert leaves the station in the morning, dispatch sounds the alarms, and when Roy and John are in the squad while the dispatcher begins talking, there are nice reflections of the camera, reflector screen (in the background), and crew members/cameraman who move around, that are visible on the surface of the spotlight. Additionally, the shadow of the boom/mic is perfectly visible on the windshield as it moves down.
Revealing mistake: When Johnny and Roy are crawling on the balcony, during the fire at the apartment complex, when they pass under a window we can see the FX tubes from which the flames shoot out.
Visible crew/equipment: At the apartment complex fire, after Roy removes the ladder from Engine 51, the Pasadena engine rolls up, and when the Pasadena Captain walks toward Captain Stanley, the second cameraman wearing a brown blazer can be seen standing on the very top of Engine 51 to the left, shooting the overhead footage of the Pasadena engine that was just shown.
Visible crew/equipment: When the guys wake up in the morning and walk into the kitchen, the clear reflection of the camera dolly is visible on the oven glass door as it trucks to the right, when the guys see the empty mouse trap.
Visible crew/equipment: At the apartment complex fire, when Truck 82 raises its ladder, we can see the second floor balcony behind the rig, and there is a crew member wearing a long sleeved blue shirt and white hat, standing in front of the corner apartment, where there should be smoke pouring out, but there is none. The reflection of the cameraman/crew member wearing a white hat also becomes visible in Truck 82's wing mirror.
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 ★