CHICAGO — As the calendar flips to September, the Chicago Cubs are comfortably holding on to a playoff spot. But even after Monday’s 17-3 win over the first-place Milwaukee Brewers, the division looks like a long shot. If they can complete a four-game sweep this week, perhaps that discussion can be had again.But for right now, this month is important for other reasons. Here are four things the Cubs would love to see happen over the next few weeks as they prepare for October.One more starter steps up alongside Clay HolmesClay Holmes was brilliant Monday night, working six shutout frames. This is largely who he’s been all season long, aside from his last start before heading to the injured list and his first start coming off it. With the Cubs, Holmes has a 1.55 ERA in 29 innings pitched with a ground-ball rate approaching 70 percent. If the playoffs started today, he’s the team’s clear No. 1 starter.But who comes in next? That battle is likely between Kevin Gausman and Matthew Boyd. Gausman has made five starts for the Cubs; two brilliant ones, a pair of rough ones and a so-so outing. His peripherals look good: he’s striking out 25 percent of the batters he’s faced and walking just 6 percent. Home runs, an issue for seemingly everyone on this staff, have been biting him. Keep the ball in the yard, and Gausman likely locks in as the second starter.Boyd had a rough August. With a 5.23 ERA and 12.6 percent strikeout rate, there are legitimate questions about him entering September. He also needs to keep the ball in the yard (nine of the 15 homers he’s allowed came in August) and start missing bats at a higher rate. Can he get locked in this month and become a postseason factor?Who should win NL MVP?Joe CrisalliGet the key bullpen arms hummingOne of the more important aspects to get right this month. There’s been a lot of talk about pitchers who aren’t on the roster. Ben Brown, Edward Cabrera, Justin Steele, Shelby Miller and others have been mentioned a lot, but those in the current group need to find their best selves so manager Craig Counsell can feel comfortable calling on any of them in the playoffs.