CINCINNATI -- Johnny Cueto has ascended to a role in the Reds' rotation many hoped he would eventually assume five seasons ago when he was just a 22-year-old kid debuting in the Majors.

Cueto, now 26, is Cincinnati's undisputed No. 1 starter. Of course, that means he has the honor of taking the mound on Opening Day vs. the Marlins on Thursday at Great American Ball Park.

"I am ready for Opening Day," Cueto said. "I feel like I am the No. 1 now, but I have to keep working to stay on top. I have learned a lot and I have grown a lot."

Early during Spring Training 2008, when the team still held camp in Sarasota, Fla., there was a noticeable buzz around the cage when Cueto -- still a prospect -- and new arrival Edinson Volquez had their first session of batting practice against Reds hitters. Both were bringing nasty mid-to-high 90-mph fastballs and sliders with nasty movement.

At the time, Cueto wasn't even a candidate for the big league rotation. His reputation grew with each spring outing until he forced the club's hand.

April 5: Reds 4, Marlins 0
W: Cueto (1-0)   L: Buehrle (0-1)
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"I was evaluating the team on the fly, right up [to the end] on different guys," said Reds manager Dusty Baker. "Some people didn't think Cueto was ready."

It was Baker's first season in Cincinnati, and he didn't know all of his players' background. When it came to Cueto, Baker relied on the counsel of Tom Brown, who was then the pitching coach of the organization's high Class A team in Sarasota, where Cueto started the 2007 season. He jumped to Double-A and finished the year at Triple-A.

"[Brown] was with Cueto, and he told me he thought Cueto was ready. I really appreciated and valued his assessment," Baker said.

And just like that, Cueto was part of the big league rotation out of camp. In his debut on April 3, 2008, a win vs. the D-backs, he pitched seven innings and struck out 10 with no walks -- the first pitcher in modern Major League history to achieve such a feat in his debut.

Cueto, a native of the Dominican Republic, did not speak English publicly and was initially uneasy with the adjustment to life at the top level of the game. He missed home cooking, among other things, and gravitated to fellow Dominicans on the team like Volquez, who became his best friend.

"He was all over the place," recalled Volquez, who was traded to the Padres in December. "I remember when he made the team in 2008. I helped him out a lot and told him about what's going on in the big leagues."

Cueto finished the season 9-14 with a 4.81 ERA in 31 starts, but led all National League rookies with 158 strikeouts. Improvement came gradually as the right-hander finished 2009 with an 11-11 record before he went 12-7 with a 3.64 ERA as the No. 3 starter on the Reds' NL Central championship club.

However, Cueto was still prone to high pitch counts in short amounts of time as he kept trying for strikeouts. Bad breaks or opposition rallies could easily unravel him on the mound. At the same time, he was one of the hardest workers on the pitching staff and had greatly improved his conditioning by taking up running every day and cutting down the baby fat.

The Reds noticed the effort, and still liking Cueto's upside, they rewarded him with a four-year, $27 million contract that came with a $10 million club option for 2015. Still, Cueto had yet to really break out as a big league pitcher.

That all changed in 2011, even though the year got off to ominous start when Cueto landed on the disabled list in the first month with an irritation in his right biceps and triceps.

Reds
Projected Opening Day lineup
1 2B Brandon Phillips
2 SS Zack Cozart
3 1B Joey Votto
4 3B Scott Rolen
5 RF Jay Bruce
6 LF Ryan Ludwick
7 CF Drew Stubbs
8 C Ryan Hanigan
9 RHP Johnny Cueto
Projected rotation
1 RHP Johnny Cueto
2 RHP Mat Latos
3 RHP Bronson Arroyo
4 RHP Mike Leake
5 RHP Homer Bailey
Full 25-man roster | Depth chart

Shortly after he returned, Cueto's pitching finally went to another level. He started using a Luis Tiant-style motion where he turned his back to the hitter before the delivery. Instead of going for strikeouts, he became more efficient with ground balls.

Cueto finished last season 9-5 with a 2.31 ERA in 24 starts. In 156 innings, he walked 47, struck out 104 and gave up only eight home runs. Twenty-one of his starts had only three runs or fewer allowed.

"The first thing about Johnny is he is one of the best competitors out on the mound and one of the best competitors at anything," Reds rookie catcher Devin Mesoraco said. "If you watch him play anything in the clubhouse, even tic-tac-toe, he'd be a competitor. He never wants to lose. Obviously, that's something that helps him out on the mound."

Cueto's improved composure was one of the highlights not visible on a stat sheet. Just as things looked like they might go bad for him, he would simply step off the rubber and take a breath.

"Everybody knows what he did last year. I think he can do that his whole career," Volquez said. "He's got more experience now than he had like two years ago. The guy has what it takes to [pitch the opener]. He grew up. He's a grown man now, and he knows what he's doing."

After Aaron Harang started five consecutive Opening Days for the Reds from 2006-10, Cueto becomes the third different pitcher to take the ball in three years. Volquez did that job last year on a day that is treated like a holiday in Cincinnati, and it comes with a lot of distractions. Cueto was not concerned and expected to avoid much of the hoopla.

"I got confidence from learning a lot from Volquez and Harang," said Cueto, who still prefers to speak through an interpreter.

A September callup last season, Mesoraco did not catch Cueto in a game, but that should change come Thursday. The new battery has worked together a lot this spring, and Mesoraco already has a good idea of what he's in for this coming season.

"He has such a great feel for pitching," Mesoraco said. "He knows how to get hitters out. He's always thinking a pitch ahead, the sequences and everything. Unless you're right there close to him, it's hard to see. You either have it or you don't. It was something he was born with, and he knows he needs to study hitters and he picks up things from them. He's a fun guy to work with because he is so focused and intelligent on the mound."

Signs of someone that has grown up quite a bit since 2008.