The lead would be short-lived as the Aces allowed two unanswered runs in the following three innings for a 5-4 defeat.
Pfaadt went 3-0 with a 2.03 ERA in five starts since his promotion to the Aces on August 2.
Despite the loss, the Aces maintain a 15-7 record against the Aviators in the Silver State Diamond Challenge, presented by Nevada Donor Network.
With the game tied at four in the tenth, the Aces allowed a go-ahead run to the Aviators and could not counter in the 5-4 defeat.
The Aces improved their record to 15-5 against the Aviators in the Silver State Diamond Challenge
The Seattle, Washington, native played in 33 games with the Aces.
The Aces finished the night with two hits and were unable to keep pace with Sacramento in the loss.
Jancarlos Cintron and Jose Herrera each recorded solo homers Friday night against the River Cats.