Jackson didn't make it out of the first inning in his return from the disabled list, a 14-5 loss to the Los Angeles Dodgers on Friday.
Jackson (6-15, 6.38 ERA) recorded just two outs in his first appearance since he was placed on the DL last month with a strained right lat. He was charged with four hits and five runs in his fourth consecutive loss. Jackson is slated to start Sept. 27 in Milwaukee, the Cubs' penultimate game of the season. With his dreadful performance this year, it's unclear if he'll be making his last start for Chicago that day. The Cubs still owe him around $26 million.