Arroyo signed a three-year, $35 million contract in December and Cueto inked a four-year deal worth $27 million in January. Volquez, 27, avoided arbitration with a one-year, $1.625 million contract on Jan. 31, but turned down a four-year offer from the club.
A decision still must be made on the final two spots in the rotation, with Homer Bailey, Mike Leake and Travis Wood in contention.
The choice to lead the rotation with Volquez underscores the completion of his comeback from injury. He missed most of 2009 and had Tommy John surgery on his right elbow in August of that season. On Opening Day last year, he was back at the Reds' Arizona complex still rehabilitating and didn't make his first start with the big league club until right after the All-Star break. In the interim, there was also a 50-game suspension he served while on the disabled list for violating the MLB policy on performance-enhancing drugs.
"It's a long way," Volquez said.
Volquez went 4-3 with a 4.31 ERA over 12 starts during 2010. His last full season was 2008, his first in Cincinnati, when he won 17 games and became an All-Star for the first time.
There were times when Volquez was inconsistent following his return last year, but he posted a 1.95 ERA over his final four regular-season starts. That earned him the start in the playoff opener in the NLDS against the Phillies, but he only lasted 1 2/3 innings, with four runs allowed, while Roy Halladay tossed a no-hitter.
"I feel 100 percent right now," Volquez said. "I don't feel anything in my arm. I've been throwing a lot. Before I came here, I threw five [bullpen sessions], one live BP and two innings. I've already got three [bullpen sessions] down here."
The Reds will host Milwaukee in the March 31 opener at Great American Ball Park. The Brewers will most likely counter Volquez with their newly acquired ace, Zack Greinke.
Baker said the decision to go with Volquez came after "much deliberation" with pitching coach Bryan Price and from talking to his pitchers.
"You want to go hard, soft, hard," Baker said of splitting his starters up according to pitching power. "You want to break up Cueto and Volquez, because you don't want them to out radar gun each other."
However, those weren't the only factors. There was also a process of elimination.
"We're very confident in Volquez. Plus, you name who you think can handle it the best," Baker said. "Is Homer ready for the No. 1? Is Wood ready for No. 1? Is Leake ready for No. 1? Cueto just signed a four-year contract, and what's he, 23 years old? He's already got enough pressure on him. I'm trying to relieve any pressure from him thinking he has to prove he's worth the money.
"There's nobody looser and I think can handle the situation better than Volquez. Not much bothers him. At least he doesn't show it bothers him."
Arroyo, as the longest-tenured Reds player and a 17-game winner last season, could have been viewed as the more conventional Opening Day choice. But Arroyo passed on a chance to open last season, deferring to Aaron Harang. Harang had started the previous five openers for the Reds, but he is now with the Padres.
"I think Bronson has always leaned towards not being it," Baker said. "He's more of a long-run type of guy. What's Bronson's ERA, [3.88]? If you're facing No. 1s, that equals a lot of losses. He's fine with it. I talked to him about it. He was thinking about it this winter, he feels it's the best spot in the rotation for him, too."
Volquez understands the meaning of the opener in Cincinnati, especially since mentor and organizational pitching coach Mario Soto did it six times for the Reds.
"[Soto] told me last year, 'I want you to be the No. 1 starter here.' This year I'm getting the opportunity," Volquez said. "He was joking about his number on his back, on the back of his jersey. I wear No. 36. He said, 'Hey, you better be a No. 1 starter, because I used to wear the same number.'"
During his first camp with the Reds, after making the team in 2008, Volquez said he almost ditched No. 36 because he wanted a different number.
"Mario told me to keep it, that I would be good wearing that number," Volquez recalled. "He told me most of the pitchers with that number do something special in the big leagues. He said, 'You better keep it if you want to be something special.' I kept it."