During a break, Homer eyes the nearby box of donuts and proceeds to pig out. He shrugs off Lenny's warning that eating so fast will make him start choking, and just then, he does. As Homer lumbers around choking, Lenny looks for the chart for the Heimlich maneuver when he sees a sign-up chart for company softball. After Homer coughs out the donut, he goes to immediately sign up and asks if anyone else will be next. Lenny, Carl and Charlie all decline, but they soon change their minds after Homer tells them that he has a "secret weapon".
At home, Homer is showing Bart something very special that he made: a homemade bat. He tells the story of it's origin: one rainy night, Homer had locked himself out of the house. As he goes to ignore multiple degrees of safety logic, a bolt of lightning struck a tree branch and it dropped off the tree. Homer feels that this piece of wood, with the insides glowing, is a sign; it is to be used for a baseball bat. He shows Bart his hard work: a baseball bat he has named "Wonderbat".
In the Springfield Nuclear Power Plant's first game, they are playing against the Springfield Police Department. Once the bottom of the ninth has arrived, bases are loaded, two players are out, the score is 5 to 2 in favor Springfield's Finest, and Homer is up to bat. At this time, he finally unveils his secret weapon to Lenny and Carl: Wonderbat. They start to make jokes about it, but Homer refuses to take them seriously; this bat will help them win. Homer ends up scoring the winning run which Bart and Lisa admire.
As the series continues, Homer and Wonderbat keep their magic going throughout the season, winning against team after team. This makes the other players start to look for "magic bats" of their own.
At the Millionaires' Club, Smithers tells Mr. Burns of the team's win streak and they only need to beat Shelbyville's Nuclear Power Plant to win the pennant. While at lunch with Ari Amodopoulos, they make a bet that whoever's team wins the championship game will win a $1 million bet.
Mr. Burns wants to win the bet by any means necessary, so he wants to hire a team of professional baseball superstars to play for the plant and win. He immediately thinks of a lineup of players from his generation, but Smithers points out that all the players he is familiar with have retired from the sport, and have been dead for a long time. So, Mr. Burns sends Smithers off on a hunt to find some pros from the current generation.
At a company meeting, Mr. Burns unveils to the plant employees their new teammates: Roger Clemens, Wade Boggs, Ken Griffey Jr., Steve Sax, Don Mattingly, Darryl Strawberry, Ozzie Smith, Mike Scioscia and Jose Canseco. It seems like Mr. Burns knows exactly who he wants for the team and who he wants cut.
At the table, Homer is grousing to the family about the fact Darryl Strawberry, who is playing his position on the field, seems to have it made: whatever he can do on the field, Darryl can do better. Bart is disgusted with his father, saying he told him a long time ago that he can do anything as long as he puts his mind to it. Homer takes that statement back, saying it's a crock.
During practice, Mr. Burns tells the plant employees (and the pros) that if they want their place on the team, they will have to earn it. He also introduces a new drink for the team: instead of beer, they will be drinking a Brain and Nerve Tonic that will improve health (but at a risk at a rare case of gigantism). He offers a taste to Ken Griffey Jr., and is instantly hooked.
While Homer's rivalry with Darryl Strawberry continues, Mike Scioscia is happy with his job working as a janitor for the plant. In addition, despite Don Mattingly's objections that he is not wearing sideburns, Mr. Burns tells him to get rid of them. When Homer gets a chance to bat, he does not think the professional players will be so tough: after all, he's still got Wonderbat. But a fastball thrown by Roger Clemens makes short work of Wonderbat.
That evening, Mr. Burns tells the players the Springfield Nuclear Power Plant softball roster has been finalized and will be posted shortly. Once Smithers posts the list, it looks good for the professional players, but lots of plant employees appear to be cut. Homer is anxious about his chances of making the team. Roger Clemens tells Homer he made it, but apologizes for mistaking him for Ken Griffey Jr. Homer is disappointed as this news can only mean he was cut.
Mr. Burns finishes assigning positions for the pro athletes, knowing that with a team of players who eat, drink and breathe professional baseball, he has no chance of losing his bet to Ari Amodopoulos. The only way he can lose is if all the professional players fall victim to different misfortunes, aliments and other problems, but scoffs at the idea of that happening.
However, Mr. Burns' wish is the writers' command. On the day of the big game, after he tells Don Mattingly to get rid of his sideburns for the last time, all the pro athletes are seemingly gone and Mr. Burns demands Smithers to tell him where they all are. Smithers gives the answers: Steve Sax got arrested for an unsolved murder in New York City, Mike Scioscia is suffering radiation poisoning from his work at the plant, Ken Griffey Jr.\'s constant swilling of Brain and Nerve Tonic had caught up with him and is now suffering gigantism, Wade Boggs got in a bar fight with Barney Gumble and lost, and Ozzie Smith seems to have disappeared off the face of the Earth. In addition, Jose Canseco is still acting as a hero for a woman whose house is on fire, and no thanks to the plant's hypnotist, Roger Clemens was hypnotized into thinking he is a chicken. When Don Mattingly comes back, a whole portion of hair on his head is gone and the now furious Mr. Burns kicks him off the team permanently. Now with the professional baseball stars gone, Mr. Burns has no choice but to play the plant employees. The only player forced to sit out is Homer, because Darryl Strawberry is still perfectly functional. Bart and Lisa start to razz the final pro ball player, who continues to score for the team.
As the game has reached the bottom of the ninth, the bases are loaded, there are two outs, and Darryl Strawberry is up to bat. Homer, who never once got a chance to play, thinks that the team will win, while he never had a chance to do anything. But just then, Mr. Burns decides to play the percentages by swapping Darryl Strawberry, a left-handed player (the pitcher is also left-handed), with a right-handed player. Homer is called up to bat and thinks to himself as Mr. Burns explains the hand signals. When he is up to plate, Homer is confused by what Mr. Burns' hand gestures mean, when he is beamed in the head by the ball, knocking him unconscious. Marge thinks something terrible just happened, but Lisa explains that because Homer was hit by the pitch, that counts as a hit and Homer won the game.
Indeed, the Springfield Nuclear Power Plant wins, and the plant employees hold the still unconscious Homer over their heads in victory. The team (including the various pros who suffered different misfortunes) gather for a picture.