Ramirez became a free agent after the 2011 season and signed with the Brewers, before returning to Pittsburgh before the July 31 non-waiver Trade Deadline. Now, he and Castro will square off tonight in the National League Wild Card Game presented by Budweiser, live on TBS at 8 p.m. ET/7 p.m. CT.
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This season, Ramirez came through for Castro again when Cubs manager Joe Maddon decided to make a switch and start rookie Addison Russell at shortstop. Castro, a three-time All-Star, found himself on the bench.
"He called me," Castro said of Ramirez. "We went to eat together, and we talked a little bit. He told me, 'Trust yourself and don't let any negative thing put you down. Keep working, you know you're good.'"
Ramirez's message was one of the elements that helped Castro get back on track. The Cubs' infielder was batting .236 when he was benched; he led the National League in batting in September, hitting .426.
"He's pretty good," Castro said of Ramirez. "He'll always talk positive. He has always been real. If he has to tell you something, he'll tell you to your face, he won't talk behind your back."
Tonight's contest could be Ramirez's last game. The third baseman, who is back with the team that originally signed him in 1994, has said this will be his final season.
"I told him, 'You can play,'" Castro said of his message to Ramirez. "He said, 'No, I don't want to. I know I can, but I don't want to any more.'"
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.