In an effort to learn what his reserves can do under game conditions, Coach Dolph Samborski of the freshman baseball team will start an almost completely new lineup against Governor Dummer Academy this afternoon at South Byfield.

Second baseman John Canepa and centerfielder Bob Smith will be the only starters today who were in the opening lineup in Wednesday's victory over M.I.T. Canepa, the acting captain, played for Dummer last year.

Samborski, who expressed pleasure with his team's performance against M.I.T., has nominated righthander Fred Rhinelander and lefthander Scott Ricketson to share pitching duty today. Starting pitcher for Dummer, which has lost its only start so far this season, will be Samborski's son, Paul.

The starting lineups: HARVARD  GOV. DUMMER Canepa, 2b  Flynn, lf Knowlton, rf  Kelley, 2b Smith, cf  Fisher, 3b Arnow, lf  Zins, ss McCusker, 3b  Jaquith, cf O'Connor, 1b  Robb, rf Carlevale, ss  George, 1b De Rahm, c  Dickerman, c Rhinelander or  P. Samborski, p Ricketson, p