Defending champion Becky James qualified second quickest in the women's sprint on day three of the Track Cycling World Championships in Cali, Colombia.
The 22-year-old from Abergavenny finished her flying 200 metres in 10.954 seconds, behind only world record holder Kristina Vogel of Germany, who clocked 10.946secs.
The qualifying determines seedings for the match sprints and saw James paired with Holland's Shanne Braspennincx.
James' British team-mate Vicky Williamson was surprisingly quick in qualifying in fifth in 10.999, while Jess Varnish was the sixth fastest in 11.045.
Olympic champion Anna Meares of Australia was given seventh after recording the same time as Varnish.
Williamson was paired with Diana Garcia of Colombia in the first round, Varnish with Kayono Maeda of Japan and Meares with Anastasiia Voinova of Russia.
Ed Clancy, the 2010 world champion, had a strong start in the first of six disciplines in the men's omnium.
Clancy is a strong exponent in the three timed events and led the field in the flying lap, clocking 12.806 as the only rider to go beneath 13 seconds.
James let Braspennincx lead out the sprint in the one-on-one duel before overtaking comfortably entering the home straight to win by a bike length.
Williamson, 20 from Norfolk, showed great maturity to deal with the partisan din in allowing Garcia to pass her entering the final lap before rounding her Colombian opponent to win by half-a-bike length.
Varnish also advanced into the second round by dispatching Maeda with ease.