|Created by||Hideo Kojima|
|Relatives||Meryl Silverburgh (wife)|
|Voice Actor (En)||Dean Scofield (MGS, MGS2)|
Beng Spies (MGS4)
|Voice Actor (Jp)||Naoki Imamura (MGS, MGS2, MGS3)|
Jun Fukuyama (MGS4)
Until MGS4, Johnny only played minor roles within the story. He is an American soldier who is often plagued by diarrhoea on his missions, which Johnny claims is brought on by him being around beautiful women.
In Metal Gear Solid, he initially guards Meryl's cell while she is being held captive by Liquid Snake. Meryl escapes and mugs Sasaki of his clothes, leaving him naked and dazed on the floor in the gunfight which breaks out. Sasaki is later assigned to guard Solid Snake when he is captured by Sniper Wolf, but his stomach becomes his downfall as Snake takes advantage of Sasaki's toilet break and, with the help of either Otacon or Gray Fox, escapes from the cell.
Sasaki is also present in the attack on Big Shell in Metal Gear Solid 2: Sons of Liberty. While Raiden listens in on a conversation between Revolver Ocelot and Solidus Snake, Sasaki relieves himself and muses over his feelings about the Russian soldiers on the plant. He also hides on the sea level route between Strut L and Strut E, and in a hidden scene warns Emma to leave Big Shell before it sinks, before having to leave to relieve himself.
Although Johnny himself is not in Metal Gear Solid 3: Snake Eater, his grandfather (also named Johnny) is. If the player throws the vampire bat given to them to eat back out of the cell, Johnny will eat it and will suffer from diarrhoea.