Stetina broke his tibia and patella on his right knee when he crashed into an unprotected bollard in the road during the finish of stage 1 of the Vuelta a Pais Vasco on April 6 this year.
In June, Stetina reported a breakthrough in progress after having the wiring that held his kneecap together removed, and he began to aim to return to racing before the season's end.
"All of the doctors who have seen Peter cannot believe his determination," BMC's team doctor Max Testa said in a press release. "He did not want to miss this opportunity to return to racing in the U.S. The team will not put any pressure on him, either. He will have to take the race one stage at a time and see how he feels."
Phinney's rehabilitation has taken much longer due to the severity of his injury. He has been out of competition since May, 2014, when a motorcycle stopped in his path on the descent from Lookout Mountain in the USA Cycling Professional National Championships. He suffered a compound fracture of his tibia, a disclocated fibula, shattered his kneecap, and severed his patellar tendon when he crashed into a guard rail.
Initially, Phinney hoped to return at this year's Tour of California, but had to scale back those ambitions when his recovery did not progress as quickly as he would have liked.
BMC general manager Jim Ochowicz told Cyclingnews in May that he wanted Phinney to race this season "just for confidence", with an aim at being full strength for next year's Classics.
Phinney confirmed his participation in the Tour of Utah on Friday, writing, "Happy to announce that I'll be racing the Tour of Utah, starting Monday. Thank you to the many beautiful souls who have helped get me back!"
A team official confirmed that Stetina would participate.