After just two more Triple-A starts, Parra made his major league debut on July 20 against the San Francisco Giants. Coming on in relief, he surrendered no runs over  innings and struck out 3 of the 4 batters he faced. Parra appeared in eight more games, including two starts, before breaking his left thumb during a bunt attempt in a game on August 30, which forced him to finish the season on the disabled list. Parra ended the campaign with an 0–1 record and a 3.76 ERA in 9 games with the Brewers.