The veteran righthander should have started against Detroit for the next step in his buildup to the regular season, but he was on Field 4 of the CenturyLink Sports Complex, pitching to minor leaguers.

Field 4 is one of five full-sized fields that are used for the development of Twins prospects for most of the year, with some used as workout fields for the major league team during spring training. There's an observation tower in the middle of three of the fields, from which music is played.

It's a more relaxed vibe, and it's where Odorizzi turns a hypothesis into theory. It's where Odorizzi can work on pitches without scores being kept or opponents seeing what he's working on.

"Actually I kind of prefer it more so because this is what spring training's for," he said. "It's the work, and I think sometimes you get out of your working mind-set. Over there you're like, 'All right, I need to get outs. I need to get through the inning,' whatever it may be so you kind of revert to what you might not want to work on at the time I guess is the right way to put it. I'm always a fan of doing this."

So Odorizzi threw 52 pitches over three "innings" on Tuesday. He threw around 15-18 pitches an inning, then would sit down in the dugout as if he was a real game, as another Twins pitcher threw an inning. Minor league hitters dug in against Odorizzi, but few made contact.

That's how Odorizzi collects data, making mental notes of how the hitters react to his pitches more so than where they are hitting the ball. On Tuesday, the goal was to perfect his off-speed pitches, and the altered swings served as positive reinforcement that he was on the right track. Pitching coach Wes Johnson wasn't far away, chatting with Odorizzi between innings.

"Good," Odorizzi replied when asked if he liked the results, "and I think too I like the way they look, but I like to see the hitters' reactions or swings and that's just something that you can't get in a bullpen.

"You can work as much as you want, like the shape and everything, but until you see hitters' reactions and how they see it and how it looked to them and the swings that they take on it — I think that's what's important about it so that's why these settings are really perfect for that. I'm working on the higher end of effort, and I get to see guys and how they react to those pitches as well, instead of just picturing in my head in the bullpen, 'Oh that one was really nice. I wonder what would have happened?' "

It's also important for Odorizzi to see how major league hitters handle his pitches. That will eventually happen as he builds up to 65, 80 and 95 pitches before Opening Day. And he doesn't think it hurts to avoid teams that he might face during the season — especially on Tuesday with American League Central foe Detroit in town.

For now, Odorizzi, who turns 30 on March 27, deserves such leeway. He's coming off his best season as a pro, going 15-7 with a 3.51 ERA in 2019 while being named to the All-Star team for the first time. It comes after he recalibrated his mechanics during the previous offseason, as he realized that he had gotten into some bad habits in 2018, his last year with Tampa Bay before being traded to the Twins during spring training.

Instead of testing free agency following his breakthrough 2019 season, Odorizzi accepted the Twins' qualifying offer of $17.8 million for 2020. He might have cashed in if he had declined the offer, but another strong season will make him one of the most coveted starters on the next free agent market — unless the Twins approach him with a long-term deal, which he would be eager to see.

For now, he's betting on himself to take his game to another level, so he's preparing for the season the best way he feels. And that's through tinkering with his pitches in a control setting before unleashing them against the league.

"Odo's very comfortable doing that," Twins manager Rocco Baldelli said. "He doesn't feel like he needs to be on the stadium mound for all of his mounding. There's a guarantee you're going to get out there and get the amount of work you want to get in.

"When you take the mound and the back field, if you want to throw 55-60 pitches, you can. You can up-down yourself as many times as you want. You can really attack the situation any way you want. I think he likes having the ability to do that one or more times during the spring. I could see him potentially doing that again."