By Bruce Levine- 

CHICAGO (CBS) — MLB rosters expand Friday, when teams can add any number of players they wish who are on their 40-man roster.

The Cubs will promote reliever Justin Grimm, catcher Victor Caratini, right-hander Dillon Maples and infielder Mike Freeman. Maples hasn’t appeared in a big league game yet, while the Cubs recently scooped up Freeman on a minor league deal after he was with the Dodgers earlier this season.

Those additions will take place Friday morning. To add Maples and Freeman, the Cubs must open two spots on their 40-man roster.

September roster expansion is criticized in some circles, as the odd month can change the equation of games. Specifically, it can help provide cover for teams with bad bullpens, allowing them to match up better. Teams that are hopelessly out of the playoff race can match up well nearly every batter from the sixth inning on just by adding a handful of relievers to their bullpen.

“I am all in favor of extended rosters,” Cubs manager Joe Maddon said. “I just don’t think it should be over 30. It is becoming a pretty common thought that it is OK to expand but limit the number on a nightly basis. The biggest part of that is the bullpen matchups. That factor really shows up when you are playing a team who isn’t in it. They can just keep matching up to lefties and righties until you are matched up to oblivion. They can expand to 40 men. I don’t care as long as they limit the number active each night that you must declare before the game.”

The Cubs will rely on the same players who have helped them build a 3.5-game lead in the NL Central entering play Thursday night. The difference is that in blowouts, they’ll have extra players to use and rest some of the regulars.

“The last month of the season is kind of a year into itself,” Cubs catcher Alex Avila said. “The atmosphere is almost like spring training only the games mean a lot. With new players means more preparation and reading scouting reports.”

Avila agrees with Maddon about limiting rosters to a certain number of active players each game.

“Each team should have a limit on a particular day,” Avila said. “I don’t think it is fair if one team has 32 players and the other has 28. They should have a certain amount that is equal or a limit each game. I heard people suggest you can only have 30 men on the roster each game and be able to change them each series. It definitely should be looked at.”

Bruce Levine covers the Cubs and White Sox for 670 The Score and Follow him on Twitter @MLBBruceLevine.

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