Ethiopia's 10 000-metre runner Tirunesh Dibaba and New Zealand shot-putter Valerie Adams both produced world best performances in the eastern Czech city of Ostrava.
Jamaica's Powell, the Olympic relay champion from 2008, crossed the line in the 100-metre race in 9.97sec, improving his season's best of 10.02sec, but referees called the runners back over a false start when the pack was more than halfway through the race.
Half an hour later, the 30-year-old Powell covered the distance in 10.06sec, ahead of Kim Collins of St Kitts and Nevis and US sprinter Mike Rodgers.
"I was a little disappointed the first run did not make out. I'm happy to win but not satisfied with the time," Powell said.
Powell was originally scheduled to run a relay against the Racers Track Club's team featuring Usain Bolt and Yohan Blake, but the Jamaican stars pulled out, forcing the organisers to insert a 100-metre race instead.
Reigning 100m hurdles Olympic champion Sally Pearson returned to the track after being sidelined for almost a year, winning her race in 12.67sec.
"The time is a good sign for the world championships in Moscow, but I definitely wanted to run faster," said the Australian.
"I haven't competed for eleven months, therefore I'm satisfied with the result," she added.
Ethiopia's reigning Olympic champion Tirunesh Dibaba set the year's best time in the 10 000 metres, clocking 30min 26.67sec but complained about the cold breeze on an otherwise sunny day.
"I'd say I could run much faster but it was a little bit windy and the pacemaker did not run the way I wanted," she said.
Compatriot Kenenisa Bekele, triple Olympic champion yet uncertain of a spot at the world championships in Moscow in August, could only finish fourth in the 5,000 metres, overshadowed by another Ethiopian runners, 19-year-old Edris Muktar.
New Zealand's Valerie Adams, also a champion from London, scored this year's best in shot put with 20.88 metres.
"I improved attempt by attempt and hopefully the 21 metres mark will be reached soon. This is a good sign for the world championships," said Adams.
Grenada's Kirani James, another London winner, took the 400-metre race in 44.49sec.
Kenya's 18-year-old prodigy Conseslus Kipruto won the 3 000-metre steeplechase while compatriot Milcah Chemos dominated the women's race.
Results Thursday from the Golden Spike, part of the IAAF World Challenge series (all distances in meters):
Men:
100m:
1. Asafa Powell, Jamaica, 10.06 seconds. 2, Kim Collins, St. Kitts and Nevis, 10.08. 3, Mike Rodgers, United States, 10.16. 4, Adam Gemili, Britain, 10.19. 5, Jimmy Vicaut, France, 10.23. 6, Gabriel Mvumvure, Zimbabwe, 10.41.
400m:
1. Kirani James, Grenada, 44.49. 2, Wayde Van Niekerk, South Africa, 45.09. 3, Pavel Maslak, Czech Republic, 45.22. 4, Brian, Gregan, Ireland, 45.55. 5, Nigel Levine, Britain, 45.93. 6, Michael Bingham, Britain, 46.24.
800m:
1. Mohamed Aman, Ethiophia, 1:43.78. 2. Andre Olivier, South Africa, 1:44.45. 3, Anthony Chemut, 1:44.69. 4, Ferguson Rotich, Kenya, 1:44.93. 5, Kevin Lopez, Spain, 1:45.01. 6, Rafith Rodriguez, Colombia, 1:45.18.
5 000m:
1. Edris Muktar, Ethiopia, 13:03.69. 2, Augustine Choge, Kenya, 13:06.37. 3, Lawi Lalang, Kenya, 13:07.13. 4, Kenenisa Bekele, Ethiopia, 13:07.88. 5, Sergio Sanchez, Spain, 13:12.97. 6, Cornelius Kangogo, Kenya, 13:17.19.
3 000m Steeplechase:
1. Conseslus Kipruto, Kenya, 8:11.27. 2, Roba Gari, Ethiopia, 8:24.30. 3, Timothy Toroitich, Uganda, 8:27.34. 4, Wilson Maraba, 8:28.21. 5, Steffen Uliczka, Germany, 8:28.49.
High jump:
1. Bohdan Bondarenko, Ukraine, 2.28. 2, Jaroslav Baba, Czech Republic, 2.25. 3, Mickael Hanany, France, 2.25. 4, Aleksey Dmitrik, Russia, 2.25. (tie) Mihai Donisan, Romania, 2.25. 6, Peter Horak, Slovakia, 2.20.
Pole vault:
1. Renaud Lavillenie, France, 5.92. 2, Otto Bjoern, Germany, 5.72. 3, Raphael Holzdeppe, Germany, 5.62. (tie) Augusto De Oliveira, Brazil, 5.62. (tie) Jan Kudlicka, Czech Republic, 5.62. 6, Hiroki Ogita, Japan, 5.62.
Javelin:
1. Vitezslav Vesely, Czech Republic, 87.58. 2, Guillermo Martinez, Cuba, 84.39. 3, Lukasz Grzeszczuk, Poland, 81.27. 4, Stuart Farquhar, New Zealand, 77.64. 5, Petr Frydrych, Czech Republic, 72.44. 6, Oleksandr Pyatnytsa, Ukraine, 71.44.
Women:
1 500m:
1. Sifan Hassan, Netherlands, 4:04.02. 2, Susan Kuijken Netherlands, 4:05.38. 3, Violah Lagat, Kenya, 4:05.66. 4, Kalkidan Gezegehne, Ethiopia, 4:06.19. 5, Zoe Buckman, Australia, 4:06.36. 6, Corinna Harrer, Germany, 4:06.60.
10 000m:
1. Tirunesh Dibaba, Ethiopia, 30:26.67. 2, Gladys Cherono, Kenya, 30:29.23. 3, Belaynesh Oljira, Ethiopia, 30:31.44. 4, Yeshaneh Ababel, Ethiopia, 30:35.91. 5, Sule Utura, Ethiopia, 30:55.50. 6, Linet Masay, Kenya, 31:02.89.
3 000m Steeplechase:
1. Milcah Chemos, Kenya, 9:17.92. 2, Hiwot Ayalew, Ethiopia, 9:19.87. 3, Purity Kirui, Kenya, 9:26.50. 4, Etenesh Diro, Ethiopia, 9:26.60. 5, Fancy Cherotich, Kenya, 9:28.04. 6, Svitlana Shmidt, Ukraine, 9:37.33.
100m hurdles:
1. Sally Pearson, Australia, 12.67. 2, Lucie Skrobakova, Czech Republic, 13.02. 3, Andrea Bliss, Jamaica, 13.03. 4, Cindy Billaud, France, 13.12. 5, Nooralotta Neziri, Finland, 13.24. 6, Lavonne Idlette, Dominican Republic, 13.36.
400 hurdles:
1. Zuzana Hejnova, Czech Republic, 53.32. 2, Denisa Rosolova, Czech Republic, 55.12. 3, Lauren Boden, Australia, 55.55. 4, Tracey Ristananna, Jamaica, 55.98. 5, Meghan Beesley, Britain, 56.08. 6, Yadisleidy Pedroso, Italy, 56.13.
Pole vault:
1. Yelena Isinbayeva, Russia, 4.78. 2, Yarisley Silva, Cuba, 4.72. 3, Jirina Svobodova, Czech Republic, 4.62. 4, Anastasiya Savchenko, Russia, 4.52. 5, Romana Malacova, Czech Republic, 4.32.
Shot put:
1. Valerie Adams, New Zealand, 20.88. 2, Natalia Duco, Chile, 18.18. 3, Anita Marton, Hungary, 17.63. 4, Melissa Boekelman, Netherlands, 17.63. 5, Anca Heltne, Romania, 17.48. 6, Shanice Craft, Germany, 16.79.