Pinches was a member of Great Britain's 2012 Olympic squad that finished sixth at the Olympic Games in London. She also won the balance beam title and was second in the all-around and vault at the 2012 British Championships. In 2011, she won bronze medals in the all-around, uneven bars and floor exercise at the British Championships, and in 2010 and 2011 she won all-around silver at the English Championships before winning gold in 2012.
Pinches, who trained at City of Liverpool Gymnastics Club under coach Amanda Reddin, also competed at the 2010 and 2011 World Championships, qualifying to the all-around finals both years. She won a bronze medal on floor at the 2010 Glasgow Grand Prix.
"Jenni is not only a powerful tumbler and vaulter, but a great competitor. We're looking for her to fill in on all four events," said UCLA head coach Valorie Kondos Field. "With her wide and diverse range of interests and talents, we're extremely excited to have her join our program."
UCLA will have four Olympians on its squad in 2014 - Pinches, 2008 Olympic silver medalist Samantha Peszek, 2012 Great Britain Olympic reserve Danusia Francis and 2012 Canadian honorary team captain Christine Peng-Peng Lee. Additionally, the team will boast seven World Championships competitors in Pinches, Peszek, Francis, Lee, Mattie Larson (USA), Sydney Sawa (Canada), and Mikaela Gerber (Canada).