Chambers, in only his third race since his lifetime British Olympic doping ban was lifted, clocked a season’s best 10.28 seconds, which he still needs to improve by another tenth of a second.
However, the conditions certainly weren’t on his side as Olympic champion Usain Bolt won in 10.04 secs – which despite his sluggish start proved it was not an evening for fast times.
Lewis-Francis, who leads the British standings this summer with his 10.21 sec time in Arizona last month, clocked 10.36 secs to win the B final.
Andrew Pozzi continued his impressive recent form with a fourth place finish in a high-quality 110m hurdles race.
Pozzi once again clocked the selection standard, his time of 13.36 secs just one hundredth outside the personal best he set when winning the British student title at the Olympic Stadium nearly three weeks ago.
He also bested two British rivals, training partner Lawrence Clarke placing fourth in a 13.42 sec personal best and world bronze medallist Andy Turner coming fifth as he continues his comeback from injury.
Elsewhere, British record-holder Tiffany Porter equalled the meeting record of 12.65 secs to comfortably defeat Olympic bronze medallist Priscilla Lopes-Schliep and former world indoor champion Lolo Jones over 100m hurdles.
Olympic champion Christine Ohuruogu finished second to American rival Sanya Richard Ross in the 400m – her time of 50.93 secs outside her solid season opener in Kingston, although her early summer form appears encouraging when compared to previous successful seasons.
And Steve Lewis equalled his outdoor personal best of 5.72 metres for the second time in a month as he claimed third spot in the pole vault, in which European champion Renaud Lavillenie cleared a world leading 5.90m.
© Sportsbeat 2012
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