The BMC rider made his comeback after a 15-month layoff at the Tour of Utah last month, and showed his recovery from serious leg injuries has gone well by winning the opening stage of the USA Pro Challenge.
Phinney is aiming to earn a spot on the BMC squad for the team time trial at the UCI Road World Championships in Richmond, Virginia, as they seek to defend their world title, and is likely to be on the USA team for the time trial and road race events.
The 25-year-old spent well over a year out of competition following last year's USA Cycling Professional Road Race championship, where a race motorcycle official stopped in the middle of the descent from Lookout Mountain in Chattanooga, Tennessee, cutting off the path of the fast-descending Phinney. He crashed into a guardrail suffering a compound fracture to his lower leg, a shattered patella and injury to his tendons.
He had multiple surgeries and endured more than a year of intensive physical therapy.
The Tour of Britain begins on September 6 in Beaumaris, Anglesey and ends in London on September 13.