Theo Epstein still can't erase the Red Sox's collapse last season from his mind. Now the Cubs' president of baseball operations, he says he remembers ''stuff from 2003.'' And what happened late last season, when he was Boston's GM, was the ''toughest of all of them.'' ''At the same time, you move on,'' he added. ''You learn from it, try to get better.'' The subject came up with the Red Sox visiting Wrigley Field on Friday for the first time since 2005.