1. Justin Steele
Justin Steele is currently enjoying another incredible season at the top of the Cubs' pitching staff. With a 3.07 ERA, he is the face of the starting rotation. Early in the year, Steele went down with a hamstring injury on Opening Day, prompting him to miss over a month. The only positive from that now is he has only thrown 123 innings this year, keeping his arm relatively fresh compared to where he may have been otherwise.
The Cubs will need him to continue doing exactly what he has been doing down the stretch. If he falls short, it will take the team down with him. Although they are on the outside looking in, this team has recently rallied. This stretch of games against sub-.500 teams is make or break for them this year, and they have been able to take care of business so far.