The 26-year-old righty endured a six-start stretch from May 11-June 12 in which he went 1-4 with a 6.37 ERA, but he is 2-0 with a 0.78 ERA in his last three outings.
Hernandez said the key has been turning his body less in his delivery, and he'll be looking to keep his hot streak going in Tuesday's matchup with the Orioles at Safeco Field.
"I feel more comfortable because I'm now pitching pretty good," Hernandez said. "Before I was not doing good. I said, 'I've got to do better than this.' That's why I was so mad, because I was not doing my job. Now I'm turning it back around and my performance is good. I've got to keep it going."
Hernandez tied a career high with 13 strikeouts in a five-hit shutout on Thursday against the Red Sox, the best manager Eric Wedge said he's ever seen Hernandez pitch.
"It reinforces everything we already know about the guy," Wedge said. "He's still a young man, a young pitcher. And when you go through those tough patches you find out more about yourself. And when you come out, you come out even better. The fact I thought that last outing was the best I've seen him, I think that's what's happened. And it's not just the last one. The last three have been pretty good, but that last one was really special."
While Hernandez's last start was his best of the season, Baltimore starter Wei-Yin Chen's most recent outing was uncharacteristically poor.
The rookie left-hander from Taiwan was 7-3 with a 3.38 ERA before tying a career worst with six earned runs allowed on six hits and three walks in 6 1/3 innings on Thursday against the Indians.
"I didn't do my job, period," Chen said through an interpreter. "Everything [was] out of control and everything just went south. That's it."
Chen allowed a pair of home runs and he only attempted three curveballs, usually an important piece of his arsenal.
"Every day, you've got a different feel for your pitches," Chen said. "Today, I just didn't feel it."
The O's hope he's feeling it on Tuesday.
Orioles: Thome is on the board
Jim Thome notched his first hit as a member of the Orioles with a fourth-inning single on Monday.
Thome was 0-for-4 with two strikeouts in his Orioles debut on Sunday, and finished 1-for-3 with a walk and a strikeout on Monday.
Second baseman Brian Roberts was held out of Monday's game due to a sore groin.
The O's need only one win to ensure a winning record at the All-Star break for the first time since 2005.
Orioles shortstop J.J. Hardy is 7-for-62 (.113) in his last 15 games.
Mariners: Help is on the way
Michael Saunders, Justin Smoak and Jesus Montero are all expected to be in the Mariners' lineup on Tuesday after sitting out on Monday.
Saunders has missed the last four games with an intestinal flu, while Montero and Smoak were given the day off to try to work through slumps. Montero is hitless in his last 17 at-bats, while Smoak is 2-for-30 in his last nine games.
The trio of Saunders, Smoak and Montero has combined for 27 home runs and 84 RBIs this season.
The Mariners' bullpen threw four no-hit innings on Monday and has a 1.92 ERA in 27 games since June 2.
Thome is 8-for-16 with three homers and seven RBIs in his career against Hernandez.
The Orioles are 26-12 in games decided by two runs or fewer, while the Mariners are just 17-24.