They had no choice but to send him down. They put Gonzalez on paternity leave. This does give the ability to replace him on the roster - which they did with Farris. However, MLB rules state the maximum number of days a player can be on paternity leave is 3. Saturday, Sunday, Monday - off days count. so the rule dictates that Ferris had to go back down, it wasn't a choice they made. Gonzalez is scheduled back today (and was originally scheduled back yesterday), so unless they were going to make a different move or put him on some sort of medical leave (which I'm sure would require many more days off), they had absolutely no choice but to play yesterday with only 24 players.