A.J. Ellis doing the job every day for the Dodgers

On days A.J. Ellis is in the Dodgers’ lineup, his tasks include warming up the starting pitcher before the game.

Whenever Ellis walks down the left-field line at Dodger Stadium to the bullpen, he hears fans cheer and shout his name. Recently, he saw a fan wearing a shirt with his face on it.

“It’s so humbling, the outpouring of support,” Ellis says.

Ellis’ story as a career minor leaguer who became an everyday major league catcher at 31 has turned him into something of a cult hero.

Ellis’ on-base percentage of .436 ranked fourth in the major leagues entering the Dodgers’ day off Thursday. His 37 walks ranked sixth in the National League. He is batting .303 with six home runs and 25 runs batted in.

There was a short-lived but spirited campaign on Twitter to get him voted into theAll-Star game.

There is a website, “A.J. Ellis Facts,” which wildly exaggerates his virtues, plate discipline being chief among them. Ellis sees an average of 4.54 pitches per plate appearance, the most in the majors.

One entry on the site reads, “A.J. Ellis wonders why every pitcher he faces has Steve Blass Disease.” Another, referencing reliever Ronald Belisario’s past visa problems: “Ronald Belisario said he once saw A.J. Ellis swing at a pitch in the dirt. He was banned from the U.S. for two years.”

Ellis smiles and shakes his head.

“Everyday catcher for the best team in baseball — this is definitely surreal, something I don’t take for granted,” he says.

He didn’t expect to get this far when he was selected by the Dodgers in the 18th round of the 2003 draft. Ellis had played college ball at Austin Peay, a small school in Tennessee. “When I was drafted, I treated it as baseball graduate school — learn as much as I could about the game, try to meet as many people as I could, play for a few years,” he says.

His goal was to become a college coach.

His thinking started to change in 2006, after his first full season at double A, when he was invited to play in the Arizona Fall League, a finishing school for top prospects.

Ellis reached the major leagues as a September call-up in 2008. Russell Martin was the Dodgers’ starting catcher at the time.

Considered defensively capable but offensively limited, Ellis was viewed as a potential backup. But he had to wait. Veteran Brad Ausmus backed up Martin in 2009 and 2010.

By General Manager Ned Colletti’s estimation, Ellis was ready to play in the major leagues in 2011. But Colletti wanted three major league catchers in the organization — two on the major league roster, one in the minors as insurance.

Rod Barajas was signed to be the primary starter. Ellis still had options, meaning the Dodgers could send him to the minor leagues without passing him through the waiver wire. So he was the odd man out. Dioner Navarro, a free-agent pickup, was chosen as the backup.

When informed he would be sent down to triple-A Albuquerque last season, Ellis told Manager Don Mattingly the team was making a mistake. “The fact that A.J. fought for himself last year was huge,” Mattingly says. “It was kind of saying he thought he was ready.”

Ellis spent last year shuttling back and forth between Los Angeles and Albuquerque, compiling a .392 on-base percentage in 31 major league games.

This year, with the Dodgers in the process of being sold and lacking the financial flexibility to sign an established free-agent catcher, they settled on him as their opening-day catcher. Behind the plate, he has directed a pitching staff with a combined earned-run average of 3.12, second-best in the majors entering Thursday.

“One thing I knew about him was that he was a winner. To me, that’s more important than any other stuff,” third base coach Tim Wallach says. “He knows how to win games.”

Wallach, who managed Ellis in Albuquerque in 2009 and 2010, was always one of his strongest backers. But even he is surprised by Ellis’ level of offensive production.

In his two seasons under Wallach in the hitter-friendly Pacific League, Ellis didn’t hit a home run. “Part of the reason he’s hitting with more power is he’s attacking a little more when he’s in good hitter’s counts,” Wallach says.

Ellis also has something now that he rarely had in the minors: the label as an everyday catcher.

“It’s definitely easier to hit when you know what whether you’re 0 for 4 or four for four , you’re going to be in the lineup the next day,” he says. “That is a comfort. It does make the at-bats not as strenuous.”

Considering how well Ellis has performed, Mattingly admits he was probably ready for this role last year.

But Ellis isn’t looking back.

“You know, I used to dwell on stuff like that,” he says. “We all have our own plans, our own timetables. I had to be patient. I think it’s made me a better player, a hungrier player because of it, playing for as long as I did in the minor leagues, maturing as a player, maturing as a person.”

dylan.hernandez@latimes.com