Continuity mistake: When the patients who were treated at 86's arrive at the ER, Dix has Morton take the asthmatic boy with bronchitis into treatment 1. Then, when Roy is with Early in treatment 4, Early tells Roy to go to treatment 1 to ask Morton if he needs help, and when Roy walks into treatment 1 we can see that it's not really treatment 1, it's actually treatment 4 just playing the part of treatment 1.
Other mistake: In the bookie's apartment, on the table with all the telephones, there's a can of scouring cleanser which has the "a" and "x" covered, so all we see is the "ja" on the can, in order to hide its brand name, which is Ajax.
Fair Fight - S6-E5
Visible crew/equipment: While John's trapped with the two men in the cave-in, he digs and finds the opening to the pipe, and when he starts shouting up to Roy, the cameraman's knee/leg is right beside John's left hand, at the lower right corner of the screen. It really is.
Visible crew/equipment: At the scene of the traffic accident, after Captain Stanley tells Johnny and Roy that the victim may have a fractured pelvis, just as Johnny places the Biophone on the roof of the car the camera's angle tilts down to face the victim, and we can see the reflection of the cameraman/crew member on the car window.

Visible crew/equipment: While Brackett is on Copter 10, after the dispatcher tells the pilot that the truck driver has been heard on the CB saying that he's trapped in the cab, repeating the same location, when we see the bird's-eye view of Copter 10 flying below, the shadow of the filming helicopter is right beside the shadow of the Copter 10 chopper, at the top of the screen. (00:11:35)
Continuity mistake: When they pull the man with chest pains from the pickup truck, Dixie says treatment 3, which is opposite the receiving entrance and on the same side of the hall as the nurses' station, closest to the red line on the hallway floor, but when Dixie leaves the treatment room it's at the side of the hallway closest to the yellow line, and since there's a window on its door we know it's actually treatment 1 that he's in, not 3.
Character mistake: After Captain Stanley tells the guys about the diet and nutrition study, Cap tells Roy that he and John should go to Oceanside Park for a fire inspection, but later when Johnny's on the HT he tells dispatch to respond Engine 51 to Oceanland Park, not Oceanside Park, and then the dispatcher gives the incident address as Oceanland Park.
Visible crew/equipment: After Station 51 is dispatched to the possible heart attack, when they arrive at the scene it cuts to the interior shot of the pregnant woman walking to the door, and we can see the shadow of the cameraman moving across the lamp and curtains.
The Tycoons - S5-E23
Visible crew/equipment: After Station 51 is dispatched to the fire, a dumpster fire already put out by Phyllis, when Mike parks the engine, the reflection of crew members are visible on the jumpseat window, and the location's array lighting is visible on the engine's surface.
The Tycoons - S5-E23
Other mistake: When the patient with the heart wound is brought to the ER, the anesthesiologist brings the cart with a ventilating unit close to patient, then there are two closeups of Bird's Mark 4 unit and the bellows housing showing inflation and deflation, and on the bellows unit it reads "Animal Anesthesia Ventilator" made by Bird. This is also the same closeup we see of the ventilator unit in 4x18, "Prestidigitation," during the surgery on Brackett's father.
The Tycoons - S5-E23
Other mistake: When Roy and Johnny are with the victim who has a projectile in his heart from a lawn mower, Brackett asks for an EKG strip and there's a closeup of the Datascope monitor, even though the Datascope is not actually in the ER's base station room (it's also still in the squad at this point). Also interesting to note, when Brackett walks out of the base station and tells Early about the heart wound, Early turns the medical chart he's holding at an angle, looks down at it and it appears that he's reading his line from the chart. Then when the ambulance arrives at the scene, the stethoscope is around Johnny's neck, then it's back around Roy's neck as Johnny's lifting the patient, then it's gone from Roy's neck, and then Johnny puts it back around Roy's neck.
Fair Fight - S6-E5
Other mistake: When Squad 51 is dispatched to 'man with head injury' which is the fighting couple, the dispatcher says "10763 Riverton, cross street Valleyheart Drive," but when they arrive the two street signs at the intersection read "Valleyheart Drive 10700" and "Riverton Ave 4000." The house number is 10763, so the dispatcher should have said, "10763 Valleyheart Drive, cross street Riverton."
Continuity mistake: After leaving the football player who kicked in his TV screen, as Roy and John put the gear back in the squad, we see the old blue set of the Datascope 850 monitor and defibrillator, and not their current Datascope M/D2 white case. The last time the blue two-piece unit is even seen in the squad is in 4x13, "Parade", and the first time the white unit is used is in 4x15, "Transition", and it's then used in all following episodes. This scene was a prior taping, that was inserted into this end of the season episode.
Other mistake: When Roy and Johnny help free the man whose arm is trapped in the pipe, just as the man stands up we can see the boxes of detergent on the shelf behind him, with their brand names covered with black tape.
Other mistake: When Dixie and Mr. Hart are on the elevator, we see the number five lit up on the panel above the door as they head down to the first floor in the ER, where they meet Johnny and the kids, who get on the elevator to head up to the fourth floor. The problem is that the ER is only a 2-storey building.
Transition - S4-E15
Visible crew/equipment: When Dixie and Carol stand in the ER hallway, talking about the three accident victims coming in and being swamped, there are two tape marks on the floor near their feet, where Carol and the other nurse were standing just before Dix walked over.
Revealing mistake: When John and Roy reach the man lying near the pool with a back injury, while Thadeus keeps gnawing and grabbing at Roy's pant leg, we see the extra material that Roy has under the pants (over his socks) to prevent the dog from accidentally harming his legs.
Continuity mistake: While Roy and Johnny are with the back injury victim, his dog, Thadeus, runs off with the BP cuff, and when Roy chases him and falls into the pool, Roy's now wearing the water-type shoes, note the flat sole. Then when he and Johnny leave, the uniform shoes are back.
Camera Bug - S4-E10
Revealing mistake: When they wheel the stretcher with the unconscious teenager from the school fire into treatment 3, the stretcher is pushed up against the ER's gurney, and when the teen's right arm gets caught between the stretcher and gurney, the supposedly unconscious teen moves his arm up out of the way. Then he lifts his left hand when the attendant removes the blanket.
Welcome to Santa Rosa County - S6-E10
Visible crew/equipment: After Roy and John eat lunch with the sheriff and decide to head to the lake after lunch, when they both get into the squad car, we can see the reflection of the cameraman, who's wearing jeans and a dark shirt, in the wing mirror, as he walks closer to the car and bends down. We can also see the legs of another crew member standing behind him.
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 ★