At the 2011 Summer Universiade in Shenzhen, Shields earned the first international medal of his career, a gold, in the 4×200-meter freestyle relay for his contribution in the heats.
At the 2012 U.S. Olympic Team Trials, Shields finished fourth place in the 100-meter butterfly behind Michael Phelps, Tyler McGill, and Ryan Lochte, with a time of 51.86 [REF].