It was his first for Juve since last month's arrival from Genoa.
"This goal means many things to me," he said of his 100th in Serie A.
"Many continue to claim I am finished and journalists enjoy laughing at me, but I am still here. I'm fired up, even if not 100 per cent fit, but I am hungry to play and score for a side like Juventus.
"We have a strong squad and this is the right match for us to begin again."