Dr Russell Muirhead said he was "very pleased and relieved" at the announcement that the not-for-profit company would be running the service until at least 2018.
The contract will go out to tender to any bidder at some point after that – to the anger of some residents and campaign groups who want Shropdoc to stay.
But Dr Muirhead said it was far from a given that Shropdoc would be pushed out.
He said: "We are very pleased and relieved that this period of uncertainty is over, both for the local population which has shown fantastic support for Shropdoc recently, and also for Shropdoc staff and GPs.
"It's been quite an unsettling period during what is the busiest time of year for us.
"But we are not afraid of tendering.
"We think we have got an extremely good case, but there are some standards which we will work to, and we won't compromise just for cost basis.
"Quality does have a cost. If you have a quality front-end service, it stops people ending up in hospital or other types of care which are not appropriate for them, and they are far more costly."
Dr Muirhead said it cost about £7 million a year to run the service across the county but insisted it was worth every penny.
"We think that is good value," he said.
"We are in the lowest percentage in the country for cost per call for the patients, as we get benchmarked against the rest of the providers in England.
"Because Shropdoc is the first point of call for the vast majority of local people we have got one of the highest call rates in the country, so people do use us first.
"Because of that on a cost basis we are actually very cost efficient."
As part of the changes, people will be asked to ring the NHS 111 number from October for non-emergency care.
The Shropdoc number will remain in place alongside it for at least six months.
But it could be switched off at any point after that depending on the success of 111.
Dr Muirhead said "We have no problem at all with 111. We agree that having two choices for services, 999 or 111, does make access to services much simpler for patients, so we are supporters of the 111 ideal."