Chambers received a two-year ban and a life-time suspension from the Olympics in 2003 for using prohibited substance THG, but he remains one of Britain’s leading sprinters and will be in South Korea for the world finals next month.
The 33-year-old won at the trials event in 10.09secs ahead of Harry Aikines-Aryeetey and Marlon Devonish, who both clocked 10.14.
“I tell you what, it’s not getting any easier,” Chambers said. “My age is kicking in now. But I relish the competition because that’s what brings out the best in all of us. It keeps me on my toes.
“The main thing is I have to keep myself healthy and that’s going to be difficult because my wife had a baby girl two nights ago.
“My duties are going to be double, but hopefully I can repeat my sixth from two years ago at the World Championships.”
In the women’s race, Olympic finalist Jeanette Kwakye put her injury nightmare behind her with victory in 11.23, ahead of Anyika Onuora and Laura Turner.
Kwakye has been plagued by injuries since reaching the Beijing final and said: “It’s amazing to be back. There were times when I thought I would need a knee replacement so to be back running as fast as 2008 is a blessing.”
Meanwhile, Christine Ohuruogu insists there is no crisis ahead of the World Championships even though she finished third in the 400m trials.
Ohuruogu, who had already run the 400m qualifying time, needed to put in a late surge to come home behind hurdles specialist Perri Shakes-Drayton and Shana Cox in the 400 metres, the event in which she won the Olympic title in 2008 and World Championship gold in Osaka in 2007.
The 27-year-old has not broken 50 seconds since the Olympic final in 2008, while her season’s best of 51.49 seconds leaves her a lowly 33rd in the world rankings.
Asked about her prospects in Daegu, Ohuruogu added: “I’ll just wing it. I went to Osaka running 53 seconds so nothing’s a crisis.”