But just as he did in his first game back from a strained right calf that sidelined him nearly two months, Hernandez recovered well enough from his sluggish start and pitched deep enough into the game this time to pick up the win as he improved to 5-4 with a 3.45 ERA.
Hernandez admitted to frustration over his early issues and lack of command as he works back from a long layoff.
"A little bit," he said. "I'm not that kind of pitcher out there, giving up four runs the first two innings and then shutting down. I've got to make an adjustment."
Hernandez fell behind 4-2 after two frames in his previous outing against the White Sox, finishing with a no-decision when Seattle rallied for an 11-inning win after he'd allowed 10 hits and five runs over 6 2/3. This time he allowed nine hits and the four runs with one walk and three strikeouts in a 99-pitch outing.
"It was kind of the same. I didn't have good mechanics at all," Hernandez said. "I was missing a lot of pitches in the middle of the plate. Then I finally settled down and made some good pitches.
"I didn't have a curveball today. The slider was OK, the changeup and fastball were up. That's what you get when you've been out for a long time."
Manager Scott Servais said his ace clearly needs to be sharper early in order to have success going forward.
"The dominant pitch for Felix the last few years has certainly been the changeup, and since he's come back, he hasn't had a real good feel for that," Servais said. "It's usually a wipeout-type pitch and it just hasn't been there.
"We're trying to get through it with his breaking stuff. He made some mistakes with the fastball tonight, on the 0-2 pitch to [Starling] Marte early in the game and the pitcher hits a home run off him. He's just not real sharp."
Catcher Mike Zunino, who has seen a lot of Hernandez over the last four years, said the 30-year-old is still making mechanical adjustments as he regains his form after the longest midseason layoff of his career.
"He was just up in the zone a little bit today," Zunino said. "I think he's still finding his rhythm a little and was just up. But typical Felix, he keeps us right there in the ballgame for as long as we need it and we were able to score some runs that really helped him out. He went through six and got out of there, which is huge for us."
In Hernandez's mind, the solution is pretty simple.
"I feel fine [physically]," he said. "I have no problems at all. I just have to get out of the middle of the plate. I need to pitch a little more and I'll be better."
Hernandez's next start will come on Sunday night against the Cubs at Wrigley Field.