Duckworth did not have to strain himself much to win the first set, but it was Purcell, who rallied to win 3-6 7-5 7-6 (5) in the final.
Nagal entered the tournament through the qualifying rounds, whereas Jung entered as a lucky loser.
Purcell rallied from a set down to beat De Alboran 5-7, 7-6, 6-4 in a final that lasted over three hours.
Nick Kyrgios and Thanasi Kokkinakis defeated third-seeded Marcel Granollers and Horacio Zeballos in Australian Open 2022 men’s doubles semifinal.
It took Nagal an hour and 22 minutes to secure a 6-1 6-4 win over Jay Clarke of Great Britain.