"At Wimbledon I handled the pressure and expectation extremely well that day and played a near flawless match," Hewitt said at the Kooyong Lawn Tennis Club.
"But a lot's happened since then and I've still got to go out there and play my game...It should be a good match."
Hewitt holds a 3-2 record over 29-year-old Nalbandian, but the Argentine has won their past two. Nalbandian has also been in good form and will contest the final of the Auckland Open with top seed David Ferrer after knocking out Spaniard Nicolas Almagro.
Gael Monfils later defeated 11th-ranked Jurgen Melzer 2-6 6-2 7-6 in a hard-fought semi-final.
The Austrian had earlier defeated Frenchman Jo-Wilfried Tsonga 8-6 in a pro-set hastily arranged after rain completely washed out the second day of the four-day tournament on Thursday.
The eight-man invitational event wraps up with the final on Saturday.
(Reporting by Ian Ransom; Editing by John Mehaffey)