Matt Garza makes his next rehab start on Thursday at Triple-A Iowa and could return to the Cubs next week if all goes well. “After Thursday I’ll make a decision,” Garza said. “They want me to get stretched out a little deeper into games, and I guess that’s what I’ll have to do now.” Garza will have to be able to go six innings for him to be ready to pitch in the majors. If not, he will have one more rehab start. How much of the decision is Garza’s to make? “I’d say a lot, based on it’s kind of my job,” he said. “All in all, it comes down to what the organization wants to do. … It’s all based on how I respond and how I feel, and how comfortable I am.” Manager Dale Sveum said “if everything goes really well and he gets himself into the sixth inning, then the decision might be easier” for the Cubs to make. “We’re all going to be in on this whole decision,” he said. Sveum said he would consider going with a six-man rotation for a week depending on matchups, but added they haven’t yet gotten that far in the decision-making process. Every starter but Edwin Jackson has started off the season strong, though Carlos Villanueva has slumped lately. Sveum already has said Jackson will not go to the bullpen, which leaves Villanueva and Scott Feldman as the only two viable candidates. Garza acknowledged it’s a tough decision for Sveum. “Well I guess that’s the best problem to have, because I want to pitch, and I’m not getting ready for no reason,” Garza said. “The guys are doing great. We’re the (fourth) best in baseball right now (in starters’ earned-run average). That’s something I have to step into a gear up for.”