The right-hander was perfect through two innings but gave up seven earned runs and 11 total as the Mariners' slide continued in Arlington, Texas.
The postgame commentary turned immediately to whether Hernandez could lose his spot in the rotation, a topic manager Scott Servais broached last week.
"We'll see," Servais said Tuesday. "You have to take a look at where we're at going forward here. The next time that spot (in the rotation) comes around, we'll be over in Houston. They've also got a good club. We've got to give ourselves a chance every time out there to win the ballgame. It's tough to win."
Hernandez has lost four consecutive starts and has a 7.85 ERA in his past six outings.
"Yeah, I'm frustrated. What can I say? What can I say?" said Hernandez.
The 32-year-old has a career-worst 5.73 ERA in 23 starts.
"I lost my command after the first two innings," Hernandez said. "Just leaving it in the middle of the plate and making a lot of mistakes."
--Field Level Media