Deignan was set to ride at the Ruta del Sol, which starts on Wednesday, but has had to pull out. The 30-year-old has left his base in Monaco to head to Ireland while he recovers.
"The medical team have taken a good look at it and we've decided not to have surgery, so I'm back home in Donegal now getting ready to go again," Deignan told the Team Sky website.
This is the second time in five months that he has suffered from a broken collarbone. At last year's Tour of Britain, he fell and injured his left side. Despite the setback, Deignan remains positive that he can be back to racing soon enough. "My collarbone's a lot more mobile than the last time this happened so I'm hoping I’ll be back on the bike sooner rather than later," he explained.
It is expected that the Irishman will be able to use the home trainer in the next couple of weeks.
"It's frustrating more than anything else when something like this happens. I was happy with the way things went at the Tour Down Under and I was looking to continue building my form at the Ruta del Sol. It's not the end of the world though, it could have been a lot worse, so I'm trying to look at it in a positive way."
Deignan returned to the WorldTour with team Sky this year after two years of racing in America with the UnitedHealthcare. During his time at the team Deignan suffered from a number of health issues, which was put down to a reoccurring viral infection. He managed to conquer the infection and put in some strong performances last season, including top 10 placings at the Tour of California and the USA Pro Cycling Challenge.
Xabier Zandio will replace Deignan in the Ruta del Sol line-up. Zandio rode at the Mallorca Challenge last week.