It is nothing unusual for the 37-year-old Hernandez, who will be pitching in his 17th season for his eighth different team.
"I played in Arizona with a young team. Washington, too, is a young team," he said. "It's fun and I enjoy every moment of it. When I got here, I didn't know anybody. Now I'm more used to it."
Zach Duke and Kyle Weiland, among the other candidates for Houston's starting rotation, are also getting used to new surroundings. For Weiland, who came from the Boston Red Sox along with shortstop Jed Lowrie in a December trade, it's the first time.
"I think a lot of players think they're going to be with the team that drafted them their whole career," said the 25-year-old right-hander. "You don't think anything about being with another team until it happens. So it's a surprise, but when I found out, it was exciting because there's every opportunity here."
With the transfer of Brett Myers to the closer role, the Astros have two starting spots available behind Wandy Rodriguez, Bud Norris and J.A. Happ. Experience gives Hernandez the inside track on the fourth spot.
"Somebody has to overtake him," said manager Brad Mills.
That leaves Weiland and Duke, a 28-year-old left-hander who was a National League All-Star as recently as 2009, competing with Jordan Lyles, Henry Sosa and Lucas Harrell for the final spot. Lyles, a 21-year-old former supplemental first-round pick, started 15 games for the Astros last year. Sosa started 10 and Harrell started two after being claimed on waivers from the Chicago Cubs.
Mills said the competition is likely to go on all spring.
"They're promoting a lot of competition and that's good," said Weiland. "It's what a young team like us needs. There's a lot of opportunity for young guys like myself to try to win a spot."
Duke, a non-roster player like Hernandez, didn't sign with the Astros until Jan. 27.
"I wanted to be a starter again and they told me I would have the opportunity to prove myself in spring training," said Duke, who pitched mostly in relief in his only season with the Arizona Diamondbacks.
"It was my first time doing it, and I prefer starting," he said. "I'm more used to it, more comfortable with it. Knowing when you're going to pitch and getting prepared for that is what I'm accustomed to. If I end up in the bullpen again, that's fine, but I would prefer to start."
In his first six seasons, Duke started 160 games for the Pittsburgh Pirates, two of them on opening day. The Pirates traded him to Arizona, but a line drive in spring training fractured his left hand and he started only nine games last year.
Hernandez, who will start the exhibition opener Saturday against the Washington Nationals, has started 474 games and has pitched 3,121 2/3 innings, the most of any active pitcher.
"I still love the game. I still want to pitch," he said. "I'm 37 years old. I know I can still pitch and I don't want to retire. I feel good."