Zimmerman comes to the Aviators after spending last season in the United League with several different teams.
"[Zimmerman] will come in and try to compete for a starting spot or long relief spot," said Aviators Manager, James Frisbie.
Last season in the United League, Zimmerman posted a 5-3 record with a 4.14 ERA.
Zimmerman attended Northwestern State University of Louisiana and was drafted by the Arizona Diamondbacks organization in the 30th round of the 2010 MLB June Amateur Draft.
"Northwestern State is a good Division I program and he was a great starter for them for two seasons," said Frisbie.
Gerardo Sanchez is a southpaw pitcher from Las Cruces, New Mexico who spent last season in the Houston Astros' organization.
"I look for him to be a setup guy or a closer for us," said Frisbie. "He is definitely an impact guy for us this summer."
Last season in the Astros' farm system, Sanchez put up some impressive numbers. He finished the 2013 campaign with a 6-2 record with 86 strikeouts in 74 innings pitched.
Sanchez competed at the University of New Mexico before being drafted by the Boston Red Sox in the 42nd round of the 2009 June Amateur Draft.
Wander Ramos joins an already stellar cast of outfielders for the 2014 Rockford Aviators. He comes to the Aviators after spending the last five seasons in the Washington Nationals system.
"This guy was an All-Star in the South Atlantic League," said Frisbie. "He will bring a lot of ability, power, and speed. He will certainly be an impactful guy for us this season as well."
Ramos has a career batting average of .267 and has knocked in over 150 runs.
A native of Santiago, Dominican Republic, this will be Ramos' first season in independent professional baseball.