"Today was pretty much evaluation," said Jackson, who gave up two hits. "I see where I am with (hitters ) and try different pitches. The first couple starts you come out with a lot of fastballs. A lot of hitters are tracking it and trying to stay up the middle. I try to keep the ball down, working on things whatever they may be."
The Cubs are the 29-year-old Jackson's eighth major league team after he signed a four-year, $52 million contract with Chicago in the offseason.
"I am pretty comfortable everywhere," Jackson said. "This is not my first rodeo. I have been around the game. I have been fortunate enough to join loose clubhouses. This is definitely one of the clubhouses where everybody is having fun and taking care of business at the same time. That makes it easier to fit in and get acclimated with everything that is going on."
The Cubs are counting on Jackson to supply a solid base of innings and leadership while they put together a young pitching staff around him and Jeff Samardzjia .
"If someone wants to give me that role that is fine," he said. "I am not trying to come in and take over any ship. Everyone will be communicating, and I like to lead by example. I am not really vocal, but I can be if they need me. I just want to come in and handle business."
The Cubs and Jackson believe his best years are ahead of him despite a 70-71 career record.
"Everybody has to be that man, top of the rotation, bottom of the rotation," Jackson said. "You only pitch once a week so when it is your day you have to be that man. If the ball is in your hands then you should feel like the ace that day."