Cronin tested positive for two banned corticosteroids with Sport Ireland CEO John Treacy last month admitting that he considered the punishment to be lenient.

Sport Ireland subsequently received and reviewed the documentation of the European Professional Club Rugby investigation which was overseen by independent judicial officer Antony Davies.

Sport Ireland believe an appeal would at best lead to the ban being increased to three months.

From the outset Cronin insisted that an error was made by a local pharmacy who supplied him with the incorrect medication, due to be collected by another customer of the same name.

Davies, was satisfied that the 30-year-old had provided sufficient evidence to support that account and noted subsequently: “He (Cronin) saw his own name on the medication and sometimes players trust absolutely the environment they’re in their clubs, with the team doctor, the nutritionists, people like that and they don’t question in my view as much as they ought to do, exactly what they are asked to take.

"And in this case James Cronin didn’t and it was a careless mistake but an understandable one in the circumstances. I felt that his level of culpability was low, set against similar cases towards the lower end of the zero to two years.”

The pharmacy is now under investigation by the Pharmaceutical Society of Ireland.

Cronin's ban covered the dates from April 15 until May 16 meaning that he is now free to return when rugby resumes.

However Sports Ireland’s anti-doping chief Dr Una May told The Irish Times: “We still consider one month to be lenient.

“We could put up a huge battle to increase it to three months and could be unsuccessful. For the sake of two months it doesn’t appear appropriate to go into that level of work and detail, because there is a comprehensive file attached to this case.”