PIG ERROR : 1000

MY SCRIPT
TAB1 = LOAD '/Batting-edited.csv' USING PigStorage(',') as
(playerID,yearID,stint,teamID,lgID,G,G_batting:int,AB,G_old);

Runs = foreach TAB1 generate playerID, yearID, G_batting;

grp_data = group Runs by (yearID);

*max-runs = foreach grp_data generate group as grp, max(Runs.G_batting) as
maxrun; ==> Error here*

ERROR
========================================>-----------
org.apache.pig.tools.pigscript.parser.ParseException: Encountered " <PATH>
"max-runs "" at line 1, column 1.
Was expecting one of:

========================================>--------------

Sample data till grp_data

*TAB1*