It led to a 10-pitch duel with Brent Lillibridge, one Rodriguez barely survived. Twice Lillibridge drilled a Rodriguez fastball down the left-field line. One landed inches to the left of the chalk. The other sailed just wide of the foul pole. Rodriguez took advantage of the reprieve, striking Lillibridge out with a 76 mph curveball.
Watson entered and promptly fell behind pinch hitter Alberto Gonzalez 3-0 before battling back with two called strikes then getting out of the jam with a routine fly to center.
Marte gave the Pirates some wiggle room with a single that plated Clint Barmes in the second.
Watson and Grilli took care of the rest.
The 36-year-old Grilli, closing for the first time in his journeyman career, retired the Cubs in order in the ninth. He struck out Nate Schierholtz looking to end it and celebrated with a fist pump as fireworks exploded behind him.