In 2017, Parziale won the Massachusetts State Amateur Championship for the first time by defeating Matt Cowgill in the 36-hole final, 4 and 3. Later in the year Parziale won the 2017 U.S. Mid-Amateur by defeating Josh Nichols, 8 and 6 in the final. As U.S. Mid-Amateur champion, Parziale was invited to the 2018 Masters Tournament, where he missed the cut after shooting 81-79 (+16). Parziale also was exempt into the 2018 U.S. Open, where he tied for 48th place and tied for low-amateur for the tournament with rounds of 74-73-74-75 (+16). After the 2018 U.S. Open, Parziale played in the Massachusetts State Amateur Championship where he scored rounds of 70-70 (E) during the stroke play portion. In the first round of match play he defeated #24 seed Steven DiLisio, 5 and 3. In the round of 16 he beat #8 seed Matt Cowgill, 3 and 2. During the quarter-finals he matched up against #16 seed Patrick Frodigh and lost 3 and 2. He competed at the 2018 U.S. Amateur later in the year and shot rounds of 78-78 (+13) and failed to reach match play. As defending champion, Parziale competed in the 2018 U.S. Mid-Amateur where he T-26th in stroke play after shooting 76-68 (+2) and qualified for match play as the #34 seed. In the first round he faced #31 seed Andres Schonbaum and lost 3 and 2.