Celia Barquín Arozamena had played some of the best golf courses in the world, but her promising life ended on a humble public course down the road from her college, Iowa State University.

Ms. Barquín Arozamena, a top amateur golfer from Spain, was finishing up the first nine holes by herself on Monday morning at Coldwater Golf Links in Ames, Iowa, when a man attacked her, the police said. She was stabbed in the torso and neck, her body dumped in a pond next to the No. 9 tee box.

The killing of Ms. Barquín Arozamena, who won the Big 12 women’s championship in April, has stunned the quiet college town of Ames and led her hometown in Spain to declare three days of mourning.

Iowa State has said it will go ahead with a previously planned ceremony during halftime at the university’s football game on Saturday to honor Ms. Barquín Arozamena, 22, as the 2018 female athlete of the year. The university will also award her a posthumous diploma, granting her a bachelor’s degree in civil engineering.