CHICAGO -- The Los Angeles Dodgers have proposed a trade for Chicago Cubs starter Ryan Dempster, a baseball source told ESPNChicago.com on Thursday.

The Cubs have been clear their top priority on the trade market is adding young pitching. It is unclear whether Zach Lee, the top-rated arm in Los Angeles' farm system, is included in the offer.

The Cubs appear to be making contingency plans in case a Dempster trade is completed. A major league source told ESPNChicago.com that talks are fluid and the team is preparing to have replacements in St. Louis this weekend in case a deal is completed for the veteran starter.

In what could be the first move of an active stretch, the Cubs acquired pitcher Justin Germano from the Boston Red Sox for cash considerations Thursday.