The Italian champions looked set to open a six-point gap at the top, after Cristiano Ronaldo opened scoring in the 65th minute.
However, Fabio Borini equalized with a clever finish, before Giampaolo Pazzini struck the winner from the penalty spot.
The result means one point will separate the top three in Serie A, if both Inter Milan and Lazio win on Sunday.
“This team has been accustomed to winning comfortably over recent years and we need to get it into our heads that we cannot afford to waste points.
“We need to realise that winning cannot to be taken for granted. We must work harder, get dirty when we need to and not relax.
“Verona deserve immense credit for the first 30 minutes, but we deserve the blame for the final half-hour. They showed great intensity – we didn’t, it’s that simple,” Sarri told DAZN
Juventus have now lost twice in three games and it is their third defeat in five away league matches.
