British anti-doping chiefs have launched a strong defence of UK Sport's out-of-competition testing programme.
Ohuruogu and Don were banned for 12 and three months respectively
Commonwealth 400m champion Christine Ohuruogu was banned for a year after failing to attend three random tests.
Her ban - and that of world triathlete champion Tim Don - led to criticism that the current system was too harsh.
But UK Sport's Andy Parkinson insisted: "We cannot be serious about the fight against doping if any notice is given that a test will be sought."
Ohuruogu is currently awaiting the results of her appeal to the Court of Arbitration for Sport against her suspension, arguing that the sentence given to her by the International Association of Athletics Federations (IAAF) is notably tougher than other sports.
Don received just a three-month ban from the British Triathlon Association for the same offence.
If...the current attitude that exists among certain sports does not change we fear that the number of athletes suspended for missing tests could rise significantly
Their cases led to criticism of UK Sport's testing policy and calls from MPs that an independent agency should take control of drugs testing in UK sport.
But Parkinson, head of operations for Drug-Free Sport at UK Sport, said: "It is disappointing that we are still hearing complaints from sports about the whereabouts system.
"To provide whereabouts information and be available for no-advance notice out-of-competition tests is a fundamental responsibility of being an elite competitor."
And Parkinson warned that attempts to take drug testing controls away from UK Sport and bring them into line with independent bodies such as Australia's anti-doping agency Asada would lead to more athletes being suspended.
"The stark reality for British sport is that WADA is looking to harmonise whereabouts testing across the globe, which may well insist on the provision of information 24 hours a day, seven days a week," he said.
"If this happens, and the current attitude of some sports does not change, we fear that the number of athletes suspended for missing tests could rise significantly.
"We will fight our corner to highlight this to WADA. Our system is a good balance between the need for no-notice testing and the demands it places on the individual.
"Athletes, and particularly their governing bodies, need to realise this and do more to make it work."