Hernandez allowed three runs and six hits over 6 2/3 innings after being staked to a six-run lead in a 6-4 victory over the Los Angeles Angels on Friday night.
"David knows that it's not a start-by-start basis. It's not a tryout. He's the guy. So he needs to just relax and prepare himself to pitch whenever his turn comes up," manager Dave Trembley said. "I think he did as well tonight as we've seen out of any of our young guys this season."
"When you face that lineup, they'll make you work for it -- especially those guys at the top," Trembley said. "We've got some guys who are learning at the major league level, and for the most part we're real impressed with the progress we're getting out of our guys. I think it says a lot about the future."
Hernandez (2-2) struck out two and walked two in his fourth big league start and second since Koji Uehara went on the disabled list with elbow tendinitis. The rookie right-hander gave up a fourth-inning RBI double by Maicer Izturis, and a two-run homer by Kendry Morales in the sixth.
"Being able to throw my off-speed pitches for strikes was really huge," Hernandez said. "I was able to locate my slider and changeup and get early outs, and that's what helped me pitch deep into the game. Sometimes that's the advantage you have when you're a pitcher they haven't seen before and they don't really know what to expect."
"The guy they had tonight, he has a nice arm and good velocity. The scouting reports said he was kind of wild, but I didn't see that tonight," Torii Hunter said of Hernandez. "I remember last year we faced a lot of young guys and first-time guys, and we didn't do so well."
George Sherrill got three outs for his 18th save in 21 chances.
Ervin Santana (1-4) threw 99 pitches over five innings, allowing six runs, eight hits and three walks in his first start off the disabled list, after missing two starts because of stiffness in his right forearm and triceps.
Two of the runs were unearned as a result of shortstop Erick Aybar's fielding error -- only the third for Aybar in his last 45 games. In his four starts this season at Angel Stadium, Santana is 0-2 with a 12.12 ERA.
"You can go on rehab assignments -- but when you come back here, you've got to find the rhythm. And that's what's going to happen with Santana," Hunter said. "But you've got to give him at least a couple of starts because he hasn't pitched in a while. He still had good stuff, but right now he's not himself and he's trying to find it."
The Orioles, who came in hitting a major league-best .298 with runners in scoring position, took a 2-0 lead in the first when Scott lined a double high off the 18-foot wall in right with the bases loaded.
Scott has driven in at least one run in four consecutive games, equaling the longest streak of his four-year career. The last time he did it was May 27-30, when he homered in his first four games off the disabled list and went 8 for 15 with 14 RBIs after missing 14 games with a left shoulder strain.
Huff, who didn't have an RBI in 15 previous career at-bats against Santana, made it 5-0 in the third with his 11th homer of the season. He has 14 RBIs in his last 14 games and a team-high 55 for the season.
After the game, the Angels recalled 2B Howie Kendrick from Triple-A Salt Lake and optioned INF Sean Rodriguez to their PCL club. ... Orioles LF Nolan Reimold was named AL rookie of the month for June, after batting .320 with four homers and nine RBIs. ... Twenty-four of Morales' 26 career homers have come batting left-handed, including all 14 this season.