In the scene where Roy and his entourage meet at the Waffle House, an argument breaks out about whether the Waffle House near Salome is in Midland or Odessa. Doreen (Linda Hart) declares she is certain it is in Odessa because she is from there, settling the argument. In truth, there is no Waffle House in either Midland or Odessa.
The Actual Location of Salome, TX, appears to be the town of Rankin, TX which is located south of Midland, TX, and in between Fort Stockton, TX, and San Angelo, TX, based on the opening credits at the intersection of Texas 329, and North/South 67.
There is a brief scene during the final round of the tournament where Corey Pavin and Fred Couples (actual PGA tour pros) discuss who the unknown Tin Cup is and the amazement that would come if he were to win the tournament. Earlier in the Film it was said that Roy(Costner) and Simms(Johnson) attended the University of Houston and won several titles together. In real life, Fred Couples and CBS broadcaster Jim Nantz, who also appeared in this film, as himself, played golf at the University of Houston. Had there been even more attention to detail in the writing of the film perhaps Nantz or Couples could have mentioned knowing Roy from their college days.
During the press interview following the third of the U.S. Open, Roy McAvoy (Costner), is asked why he went for the green on 18, a "low percentage shot". He replied "So am I. ", and goes into naming his sponsors. Among the list, he says "Woody's Steak House". If you look at the shirt he's wearing, it says "Wally's Steak House", and not "Woody's".
The trivia items below may give away important plot points.
The scene at the end of the movie where Roy hits the shot into the water hazard again and again was based on an actual event. Gary McCord, the commentator with the handlebar mustache in the movie, is an actual commentator and pro golfer. In a 1987 tournament he had a shot similar to Kevin Costner's. He needed a birdie to win and went for it. He hit the water over and over again and finally made the shot, but it cost him 15 strokes. In the movie Costner gets it in 12. The scene where Roy wins a bar bet by hitting a golf ball at a pelican also was based on a real life incident from McCord's career.
During the round in which Roy qualifies for the U.S. Open, he wears headphones throughout the round. According to the USGA (United States Golf Association) Rule 14.3 strictly prohibits wearing headphone for an extended period of time. Roy should not have been able to qualify for the Open.