PHOENIX -- The knuckleballer is so focused on making the Brewers' Opening Day roster that he is barely willing to acknowledge the alternative.

"If I go back to Triple-A, that would be parts of 10 years there," said Jared Fernandez, a 34-year-old non-roster invitee to Maryvale Baseball Park. "So I feel like I'm definitely someone who has paid my dues in full. Ten years in Triple-A is too much."

Fernandez's contract has a July 1 "out" that allows him to exercise free agency if he's not in the Major Leagues, "but I don't even want it to get that far," he said. "I'm still staying positive."

That's good because "he's in the mix," according to Brewers manager Ned Yost, who, along with pitching coach Mike Maddux and bullpen coach Billy Castro, is now leaning toward opening the season with a 12-man pitching staff.

Because Fernandez's knuckleball is not as hard on his arm as, say, Derrick Turnbow's 97-mph fastball, Fernandez believes he would be a valuable middle reliever who could pitch as often as the Brewers need him.

"I like the fact that he's so durable," Yost said. "He can pitch an inning tonight, he can pitch an inning tomorrow, pitch another inning the next day. There are spots for that on your team. You don't have to worry about killing him. ... It's not a max-effort pitch."

Fernandez, who was available in the bullpen for Friday's game against the Diamondbacks in Tucson, Ariz., limited opponents to five runs and 14 hits in his first 15 Cactus League innings, good for a 3.00 ERA.

Both of the Brewers' primary catchers, Damian Miller and Chad Moeller, have handled Fernandez's knuckleball without incident.

"It made us nervous at first," Yost said. "We were wondering why were our catchers not having trouble catching it? We were wondering if it was a good knuckleball, but then the hitters tell us, 'Yeah, it's a good knuckleball, because nobody can hit it.' "

Yost added: "He just keeps getting guys out."

If he keeps getting guys out, does Fernandez have to land on the Opening Day roster?

"I don't know," Yost said. "I've got 10 days left to decide that. I'm not going to sit here and decide it today."

Fernandez traces his turnaround to last summer, when he asked for his release from the Reds after going 5-5 with a 4.38 ERA with the team's top affiliate. Fernandez signed with Philadelphia and went 4-2 with a 2.66 ERA in seven starts with Triple-A Scranton, then pitched winter ball in the Dominican Republic and was named the league's pitcher of the year.

"Maybe I was just going through the motions [with the Reds]," he said. "Somehow leaving there got me more hungry. I think I've been way more consistent at the end of last year and the beginning of this year than I've ever been.

"I'm 34 years old, and I think I've done everything I possibly can to make myself better."

Unlike some pitchers, Fernandez actually welcomes the opportunity to pitch long and middle relief.

"I've had a lot of success going through a lineup once, and before they know it, three innings are over," he said. "They don't have time to adjust to the knuckleball. I really like this role."

The next step is up to Yost and the Brewers. Will he head back to the Minors for another year of cheap hotels and bus rides, or will he head north to Milwaukee?

"I'd like to get some sleep, so I wish they would tell me," Fernandez said with a smile.

Inching back: Reliever Dan Kolb is starting to feel like himself again.

Kolb, who set a Brewers record with 39 saves in 2004 before floundering last season in Atlanta, is back with the Brewers and expected to serve as a setup man to Turnbow. After a rocky start to the spring, Kolb has impressed coaches during his two most recent outings, including a scoreless inning on Wednesday against the Rangers.

"The location -- as far as in and out -- was good," Kolb said. "Up and down, I was still in the zone, but I was at the outside of the zone. I wasn't where I want to be.

"I could pitch with that stuff all year and have a great year, but I don't want to pitch like that. I want to get back to where I was, and I'm close. I'm being a perfectionist right now."

That's good news for the Brewers, who reacquired Kolb from the Braves this winter and negotiated a discounted contract. Kolb will earn a $2 million base salary but could make more with incentives for games finished.

"He's getting stronger and stronger every time he goes out, which power-arm guys will tend to do," Yost said. "They'll go through a bit of a dead-arm period, where it seems like everything they throw up there gets whacked."

Kolb is scheduled to make his seventh appearance on Saturday against the Padres.

Back at it: First baseman Prince Fielder returned to the starting lineup on Friday after traveling to Florida to attend the birth of his second child. Fielder has just over a week to prepare for his first Major League Opening Day.

"Prince has been as good as you can expect defensively and offensively," Yost said. "Like all kids, he's going to make his mistakes, but he's very agile, he's very athletic and he's done a very, very nice job defensively."

There are questions about Fielder's defense, and he has worked extensively in camp with new coaches Robin Yount and Dale Sveum.

"He came here on a mission," Yost said. "He came ready to prove any doubters wrong about his defensive abilities."

On deck: Chris Capuano is the scheduled starter when the Brewers face the San Diego Padres at 2:05 p.m. CT on Saturday afternoon at Maryvale Baseball Park. The game will be broadcast on Gameday Audio with Bob Uecker and Jim Powell.