Usain Bolt ambled into the semifinals of the 100m Saturday as the capacity crowd at the London Olympic Stadium had their first glimpse of the Jamaican superstar.
Bolt, who is defending his 100 and 200m titles, made a slow start but eased ahead of his heat rivals to win in 10.09 seconds.
The 25-year-old world record holder has been receiving treatment for hamstring and back problems but there was no sign he was hampered by injury.
“I am feeling good, my legs are feeling good so I am happy. I am training well so I feel like I’m back. My start was good, I am only focused on the semifinals tomorrow,” he told BBC Sport after his win.
Bolt’s Jamaican rival and training partner Yohan Blake won his head in 10 seconds dead.
The 2011 world champion beat Bolt in both the 100 and 200 at their national trials and is considered a real threat to his hopes of repeating his 2008 Beijing triumphs.
Gay’s United States teammates Ryan Bailey and Justin Gatlin were the quickest qualifiers from earlier heats.
Bailey clocked a blistering 9.88 seconds, while 2004 Olympic champion Gatlin sprinted to victory in 9.97 seconds, returning to the Games after serving a four-year doping ban.
But another likely finalist, Kim Collins of St Kitts and Nevis, the 2003 world champion, failed to turn up for his heat.
He later tweeted that he had been dropped by his country after going to see his wife at a hotel.
“This can’t be right. Olympic number 5 and no Kim Collins. I hope there is an officials race.”
The early times indicated that the track was suitable for fast times and Bolt’s world record of 9.58 seconds could come under threat in Sunday’s semifinals and final.
Saturday’s qualifying races also saw ‘Blade Runner’Oscar Pistorius finish second in his 400m heat to qualify for the semifinals.
The South African, who runs with carbon fiber prosthetic ‘blades’, is the first amputee to compete in the Olympics. He is also due to compete in the 4x400m relay.
But American defending champion LeShawn Merritt hobbled out of his heat, clearly troubled by the injury that hit him in the build up to the Games.
Grenada’s world champion Kirani James and Belgium’s Jonathan Borlee, who set a national record of 44.43 seconds, impressed in their heats.