Joe Maddon is really lucky. He has five infielders to play the four positions, and all could be starters. Bryant, Russell, Baez, Zobrist, and Rizzo are all quality players. When one has the day off, the odd man out can come in at any time and the lineup doesn't suffer.
That wasn't the case for the Cubs, or really just about any team, in the 1970s. Teams had the starters and then there was a big drop off.
For the Cubs, you had Santo, Kessinger, Beckert, and Banks, and then
Paul Popovich. Popovich was great at what he did, fill in when and where needed, and do a serviceable job. Serviceable, but not anything to get excited over.
Popovich was traded before the 1974 season and he was followed by two other Popovich wanna-bes.
Dave Rosello and Mick Kelleher. As with Popovich, these two were serviceable with the glove, but not so much with the bat. Popovich was a career .233 hitter, Rosello .236, and Kelleher .213.
Popovich and Kelleher had eleven year careers, while Rosello was around for nine. In today's game, I doubt they would have lasted half as long, if that.