Montgomery and Gaines receive two-year bans
The CAS announced their decisions on the pair, who had been charged by the US Anti-Doping Agency with taking performance-enhancing drugs, in connection with the Bay Area Laboratory Co-operative (BALCO).
In a statement on the CAS website, it emerged that former double world champion Kelli White, who is also serving a two-year ban after admitting doping, testified against the pair claiming they both admitted using prohibited substances provided by BALCO.