Gorzelanny (2-3) is scheduled to make his next start on Tuesday on five days' rest.
"As far as I know, he should be fine," Russell said. "We'll just have to monitor it the next few days. It's just a tight back right now. There's no pain in his legs or anywhere else. They don't see anything in terms of nerves. It's just his muscles tightening up on him."
With two out in the fifth inning, Gorzelanny winced in pain after delivering a pitch to New York's David Wright. He threw a few warmup pitches under the watchful eye of Russell and head trainer Brad Henderson, before both gave the left-hander the green light to remain in the game.
"It just tightened up," Gorzelanny said afterward. "I've got to get it better. That one pitch was basically what happened. I wasn't leaving after that. I stayed out there, and it stayed tight."
Gorzelanny would throw three more pitches to Wright, eventually inducing a groundout to end the inning and become eligible for the win.
Russell pinch-hit for Gorzelanny the following inning, ending the left-hander's afternoon at 84 pitches. The Pirates were ahead, 8-0, at the time, and by the end of Wednesday's matinee contest, Gorzelanny would have his second win of the season.
Gorzelanny did add afterward that the tightness he felt on Wednesday was the same issue that bothered him in his April 13 start against Cincinnati. The left-hander, however, expressed no serious concern that the discomfort is a sign of a more serious injury.
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.