Andy Murray told the BBC that there needs to be "zero tolerance" when it comes to doping for tennis to stay credible.
Julian Finney/Getty Images

LONDON (AP) -- Andy Murray says Viktor Troicki and Marin Cilic were "unprofessional" and have no excuse for doping offenses that led to their suspensions.

Troicki had an 18-month ban reduced to 12 months this week for skipping a blood test in April, though he provided a urine sample that was negative.

Cilic served a four-month ban after testing positive for a banned stimulant in May. He claimed he didn't intend to ingest the substance, which was in a glucose tablet bought at a pharmacy.

Speaking to the BBC, Murray said there "almost has to be zero tolerance" for tennis to stay credible in public opinion.

The Wimbledon champion added: "Whether either player was intentionally cheating or not - we don't know that, and I don't think either of them are like that -but both of them were unprofessional."

Murray is sidelined from the ATP World Tour Finals in London this week while recovering from back surgery.

Copyright 2014 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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