Hernandez got a no-decision in Triple-A Tacoma's 8-3 win over Salt Lake. He went three innings, allowing one earned run, walked three and struck out five on 69 pitches.
"What else am I going to show them to be up there?" Hernandez told The Seattle Times. "I feel pretty good, and I'm prepared to go."
Hernandez has been on the injured list since May 12 because of a right shoulder strain.
In four minor league appearances this month, the former AL Cy Young Award winner allowed three earned runs and struck out 18 in 11 innings.
The 33-year-old right-hander is 1-4 with a 6.52 ERA in eight starts for Seattle this season. He's in the final year of his contract.
"I can't wait to go out there and pitch again," he told The Times. "It's going to be my last year. I don't know what's going to happen next year, so I need to go out there and show them that I still love the fans and still love Seattle."