The scouting report on Nolan Fontana hasn't changed: he's a high on-base machine, a label earned at the University of Florida and solidified when he reached base six times -- including five walks -- in his professional debut in 2012.

Fontana still isn't having much trouble finding first base, but he knows his path to the Major Leagues will be about more than walks.

"You've got to hit to get to the big leagues," he said.

Fontana, the Astros' second-round pick (61st overall) in the 2012 First-Year Player Draft and No. 8 overall prospect, showed some progress at the plate last season at hitter-friendly Lancaster, hitting .259 with 18 doubles, six triples, eight homers and 60 RBIs in 104 games in the High Class A California League. And, of course, he walked 102 times in 104 games for a .415 on-base percentage.

"Yeah, I've always been that guy to just get on base," Fontana said. "It's definitely something I'm working on to create a higher average. There's certain things you have to create in your game plan day in or day out, but also to keep that high on-base percentage. I guess at times it could be a double-edged sword, but it's good."

The Astros sent him to the Arizona Fall League to get him as many at-bats as possible, and the left-handed-hitting shortstop was hitting .150 (6-for-40) with eight walks and nine strikeouts through 40 at-bats covering 13 games for the Peoria Javelinas.

"It's been great," Fontana said Monday of his time in the desert. "The group of guys we're around, it's fun to come to the park every day. It's very competitive. It's something we're all enjoying, to get to create new relationships and learn some things from some other guys. That's the fun in being out here."

The AFL is considered the finishing school for Major League Baseball's top prospects. The Astros had 15 players with AFL experience on their 2013 Opening Day roster, including third baseman Matt Dominguez and pitcher Josh Fields. Pitcher Jarred Cosart, who made his Major League debut in June, played in the AFL only last year along with top prospects George Springer and Jonathan Singleton.

Fontana, 22, doesn't have the physical tools of Springer or the offensive upside of Singleton, but he's the kind of gritty ballplayer teams need and managers love. Hard work has been a baseball way of life for Fontana considering he stands 5-foot-11 and weighs 190 pounds and isn't as physically gifted as many prospects.

"You want to get better at certain things, and overall as an all-around player," he said. "With me, there's some things I'm working on with Ralph [Dickenson], our hitting coordinator, and trying to get back in the swing of things and prepare myself for what I need to work on this offseason."

Dickenson has been working with Fontana on using his lower half of his body and working from the ground up when it comes to his swing.

"He definitely got me to buy into that, and we're all really working on that right now," he said.