Pirates head athletic trainer Todd Tomczyk came out to check on Guccione, who remained in the game as Freese struck out and Sean Rodriguez lined out to third base to end the inning.
Between the first and second innings, Guccione left the game and first-base umpire Sean Barber took over behind the plate, leaving Alfonso Marquez and crew chief Larry Vanover on the bases.
It was the second time in the last three days at PNC Park that the home-plate umpire was forced to leave the game. On Monday, crew chief Jeff Nelson was struck in the eye by debris following a play at the plate and had to leave the game in the third.
Adam Berry has covered the Pirates for MLB.com since 2015. Follow him on Twitter at @adamdberry. This story was not subject to the approval of Major League Baseball or its clubs.