But the pattern of falling apart in the middle innings reared its ugly head for Jackson once again as he gave up five runs in the fifth inning. Two walks and a wild pitch helped seal his 10th loss of the season in a 9-3 defeat.
"He just couldn't control the inning," manager Dale Sveum said. "It seems like innings get out of control and they turn into big crooked numbers."
Jackson was signed to a four-year, $52 million contract over the winter to solidify a young rotation and pitch 200 innings. Neither has been the case in 2013 as the veteran pitcher has averaged just five innings per start, the fewest of the five starters. He slipped to 3-10 with a 5.84 ERA and a 1.56 WHIP.
Jackson didn't make excuses for some poorly located pitches that cost him and the Cubs the game on Tuesday.
"Stuff doesn't really matter," he said. "You see a lot of pitchers go and have good games and they don't have good stuff. Stuff comes and goes. You can still get through games without your best stuff you just have to execute pitches."
Despite Jackson's horrific first half of the season, he is not in danger of losing his rotation spot anytime soon, according to Sveum.
"There is a lot of time left, and I think he knows the formula," Sveum said. "His good games he has had the conviction and velocity without trying to finesse anybody."
On a contender, Jackson would either have been demoted to the bullpen or skipped in his next start at this juncture. Neither appear to be options for the last-place Cubs.
"Maybe (we skip him) in a perfect world," Sveum said. "You just have to go out there and pitch and have the same mentality every time."