Major league pitchers use spring training to work on new pitches, pick-off moves and technique, all while getting their arms in shape.

Diamondbacks right-hander Brandon McCarthy is almost a month into that process and said he feels like he's getting close to being ready for the regular season after his start on Friday against the A's.

"There are still some situations there, and again it's me and Miggy or me and Nieves and if I work with Rod, we're all kind of learning each other," said McCarthy. "Me and Miggy got to talk today and it's kind of the same things from last week. Guys are learning what I like to throw in certain counts and where they like to go."

McCarthy lasted four innings on Friday, allowing two earned runs while striking out six. It's the first time this spring that he's stretched his outing to four frames.

Along with his stamina, McCarthy is also in the process of working on his changeup -- a pitch he would like to use at least 10 to 15 percent of the time this season.

"This is where I want (the changeup) to be. Actually I'd like to have a day like today, an extension of that, where I can throw it a lot. If I can mix in another off-speed pitch that kind of keeps you off stuff, it gives me other avenues to go down."

McCarthy said he was able to record six strikeouts on Friday because of his changeup. He has now struck out 16 batters during the spring.

According to the first-year D-back, his off-speed pitch helps set up his other pitches and allows him to have more options when facing batters.

"The good thing is, you can throw it in games that don't matter and let guys hit it, let guys miss it, whatever it is and you can explain why I like that pitch or why I didn't, what their thought process was."

With Opening Day just 17 days away, the 29-year-old also thinks he's getting close to pitching like he would in a real, regular season game.

"That collaboration that you have for a few starts to do that is nice. It won't be completely game situation but it's getting close where I want to start putting together a game plan and executing it."