Ed Hamler is a baseball player who was injured in the leg and abandoned the game. His wife, Cindy, wants him to find a job so he won't be playing with his baseball card collection all day. Ed has a very good friend, Paula, a 12-year-old girl who also plays baseball and who one day gives him a very special baseball card. The card is from 1909 and the player in it, Monty Hanks, looks very similar to Ed. He even has the same baseball stats that Ed obtained in his first year in the majors. Unfortunately, that baseball player got hit in the face with a pitch and never played again. Ed, excited about this new special card, shows it to Cindy who seems bothered by the whole situation.
The next day, Ed goes to an interview for a job but his interviewer is busy and can't talk to him right away. Ed had promised to watch Paula's game so he leaves the waiting room and heads to the park. That night he comes back home and finds his wife is mad because he went to the game instead of the interview. Later that night, Ed is sleeping on the couch when the special baseball card starts to shine, floats through the air, and turns into a door to another time. Ed crosses to the other side and appears in 1909 in place of Monty Hanks, the player in the card. He is playing the baseball game in which he gets hit with the pitch in the face but this time Ed/Monty stands up after the hit and makes a home run. In this other timeframe, his leg works perfectly.
The next morning, Ed tells Paula how he played baseball in the past but she can't believe it. He shows her the stats on the card which now have updated and show an extra home run. Paula starts to accept Ed's story. Ed takes Paula to the past for another game of baseball although she is a little scared to do it. Once they are back in the present, Paula is very excited about the whole thing because if Ed/Monty can lead his team to another victory, they will make it to the World Series. While having dinner, Cindy tells Ed that tomorrow they are going to a reunion with some of her friends and that he might be able to find a job there. But there is a problem; he also has that special game to play.
The next day at the game, Ed/Monty can't concentrate because of his wife and the fact that he could lose her if he is not back in time for the reunion. He tells his coach that he is leaving the game but he is told that if he leaves he must never come back. He decides to stay and finish the game. When it is time to go to the reunion and Ed is nowhere to be found, Cindy decides their marriage is over and, feeling down, decides to burn all of Ed's baseball cards.
When she is burning the cards, Paula enters the house looking for Ed but instead finds a sad scene with Cindy on the floor by the fireplace, tearing the cards in half and throwing them in the fire. Paula immediately thinks of the danger Ed/Monty faces if the special card is burned so she tries to grab it but Cindy grabs it first and threatens to destroy it. After a long discussion, Paula manages to convince Cindy that the card belongs to her and not to Ed. Finally, Paula listens to some very hard things about Ed from Cindy and decides that best thing is for him to stay in the past living like a baseball star. In the end, Cindy tears the card in half and moments later notices how the stats in the card start to update very fast, meaning that Ed/Monty in the past made it big in the big leagues.