As a concerned parent, Randy radically changes the way football is played at South Park Elementary. The new version of the game quickly becomes the nation’s most popular sport. One gifted student emerges as a star athlete in Sarcastaball.
The episode begins with the boys, Butters Stotch, and Randy watching a game of football on TV when Stan Marsh tells his father that South Park Elementary doesn't let them do kickoffs when they are playing football because kickoffs are the most dangerous plays in football, which pisses off Randy. At the PTA meeting, Randy sarcastically suggests that the players should wear bras and tin-foil hats, that there should be a balloon instead of a ball, and the person who catches the balloon can run for the goal while the other players hug which he calls "sarcastaball". Mr. Mackey takes his suggestion seriously and Randy is soon the South Park Elementary Sarcastaball head coach. The sport quickly becomes very popular and replaces football. Randy is now the head coach of the Denver Broncos, and Butters takes over as the South Park coach.
That night Butters has a wet dream and saves his creamy goo, which is actually semen but is unaware of this because his father always avoids answering what it is.
Later, Cartman seeks Butters' help for sarcastaball since he is the coach and Butters gives Cartman some of his semen, which he thinks is his creamy goo. Cartman drinks the semen and thinks he feels better.
Meanwhile, Randy is confronted by Sharon Marsh who thinks something is wrong with Randy's brain because he's so sarcastic. At a South Park game it is shown that everyone is drinking Butters' semen. Randy and Sharon then go to the doctor where they found out that Randy will always be sarcastic. Randy and the doctor, both being sarcastic, come up with the idea to take the money from cancer and other genetic diseases research and make commercials about how sarcasm might be bad for your brain.
Soon after, Jim Rome recommends a new product for sarcastaball, Butters' Creamy Goo. At yet another South Park game, Randy tries to stop Stan from playing more sarcastaball. After he protests, Randy tells the crowd, trying not to be sarcastic, that sarcastaball should stop. Stan gives his dad some of Butters' Creamy Goo. Randy suddenly realizes that it is actually semen and tells Butters' parents. Butters is then confronted by his parents and became grounded for a month, despite Butters having no idea what cum is; when asked, his father says he'll answer when he's older.
When Butters falls asleep, he gets an erection, and he yells for his father. His father tells him it's his friendly compass, and that it's pointing up because Jesus is his friend. Butters then promptly thanks his dad for telling him.
AV Club gave "Sarcastaball" a "B+" rating saying: "Straddling the line between satire, silliness, and earnestness is the standard operating procedure for South Park. But given the show’s insane turnaround time (explored in depth in the documentary Six Days To Air), achieving that balance isn’t always in the cards. Either a particular episode heavily favors one factor over the others, or attempts to balance things out go astray due to the sheer pressure Trey Parker, Matt Stone, and the rest of the production team place upon themselves in order to knock these episodes out in under a week. “Sarcastaball” isn’t a classic episode of the show by any stretch. But by placing the most sincere child in the show’s universe at the center of a sarcastic maelstrom, it still produced the sweetest possible episode that also happens to feature the mass production of an energy drink composed entirely of a young child’s semen."
IGN gave "Sarcastaball" a "7.7" rating saying: "Creamy Goo aside, the boys' own sarcastaball journey was pretty forgettable. Once the initial visual of the boys running around in bras and tinfoil hats had worn off, there wasn't that much to it. Butters' motivational speeches were humorous in their own way, but never laugh-out-loud funny. Honestly, though, this was Randy's story, and in that regard "Sarcastaball" assuredly succeeded."