Reds manager Dusty Baker says the move was more of a formality.
Since Sarasota's season ends Sunday, the Reds can bring Ramirez back when the rosters expand Monday. If he was optioned to Triple-A, the Reds would be required to wait 14 days to recall him unless an injury occurred.
"He'll be eligible to be called up again [Monday]," said Baker. "Yes, it's more of a paper move. I needed another player up here. I played a man short yesterday."
To fill that void, the Reds recalled Wilkin Castillo from Triple-A Louisville.
The versatile Castillo was acquired Aug. 14 as a player to be named later in the deal which sent Adam Dunn to Arizona.
Castillo, a catcher/infielder/outfielder, hit .248 in 115 games combined at Triple-A Tucson and Louisville. He made 54 appearances behind the plate, 48 at third base, five at second base, six at shortstop and eight in left field.
When he plays, the 24-year-old Castillo will become the ninth Reds player to make his big league debut this season.
Castillo was expected to arrive at Great American Ball Park prior to game time Sunday.
"I'm told he's like an Eli Marrero," said Baker, referring to the versatile former St. Louis Cardinals player. "He can play pretty much anywhere. He's real new. I don't know much about him yet."
Ramirez allowed three runs on five hits, walked two and struck out six in the Reds' 7-6 victory over the Giants on Saturday night at Great American Ball Park. A blown save prevented Ramirez from earning his first career victory.
Ramirez was summoned as a temporary replacement for Johnny Cueto, who's been nursing a strained right elbow.
In other news, second baseman Brandon Phillips was given Sunday off. With the off-day Monday, Phillips will get a much-need two-day respite.
"He hasn't had a day off in I don't know how long," Baker said of Phillips, who's played in 133 of 136 games this season.
Jolbert Cabrera replaced Phillips at second base and batted sixth.
Jeff Wallner is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.