Stephanie Brown Trafton was unable to repeat as the Olympic champion in the women’s discus Saturday at the London Olympics and was unable to win a medal, finishing eighth overall.

Meanwhile, Sharon Day moved up two spots from her first-day placing of 18th in the heptathlon to 16th with 6,232 points.

Trafton, an Arroyo Grande High and Cal Poly graduate, placed eighth with a best of 206 feet, 8 inches. In the 2008 Beijing Olympics, Trafton won the discus when she threw 212-5 on her first throw. Her first throw Saturday was also her best, but it wasn’t enough.

Croatia’s Sandra Perkovic set a national record with a throw of 226-8 to win the event. Russia’s Darya Pishchalnikova finished second at 221-8, and China’s Li Yanfeng was third at 220-6. Perkovic was ranked third in the world entering the Olympics, Pishchalnikova was ranked No. 1, and Li was ranked fifth. Trafton was ranked sixth.

“I was in sixth going into the last three rounds,” Trafton said. “My second throw was around 66 meters (216 feet), but it was out of sector, so that was disappointing, because I was feeling kind of lackluster today.

“I didn’t have a lot of energy today, so you know having the best throw be just out of sector, who knows? I don’t know if it would have put me in medal position, but it may have given me some inspiration to throw a little farther.”

Trafton was fifth after the first of six rounds, dropped to sixth in the second round and remained in sixth until she was passed by two other throwers in the final two rounds. Trafton, who turns 33 in December, set an American record of 222-3 in May, and qualified fifth Friday for the final with a best of 212-10. This was Trafton’s third Olympics; she was 21st in qualifying in the 2004 Olympics in Athens, Greece, and didn’t reach the final.

“I’m not necessarily happy with the results today,” Trafton said, “but as a season overall, I can’t complain about being at the Olympic final, making it to the top eight. I’d love to walk out with a medal, but it just didn’t happen today.”

Day, another former Cal Poly star, dug herself a first-day hole in the heptathlon when she struggled in her best event, the high jump, and finished Friday in 18th place with 3,740 points.

Day, who turned 27 in June, had a solid second day and finished in 16th with 6,232 points, including a time of 2 minutes, 11.31 seconds in the 800, a javelin best of 144-0 and a long jump best of 19-21⁄2. Her 800 time was a personal record by more than a second and the seventh-best 800 heptathlon time overall, her best individual finish in an event in the heptathlon in London.

“I felt good about the 800,” Day said. “It was a roller coaster ride; there were definitely some lows, definitely some highs, but good overall. Sometimes you have expectations and you don’t always meet those, but with every event, you have to put them behind you and move on.”

Great Britain’s Jessica Ennis, the pre-meet favorite, thrilled the London crowd, winning with a national record of 6,955 points. Lilli Schwarzkopf of Germany won the silver (6,649 points), and Russia’s Tatyana Chernova took the bronze (6,628 points).