Veteran defender Leonardo Bonucci scored a brace to help Juventus to a hard-fought 2-1 victory over Venezia in Serie A on Sunday to all-but secure Champions League football for next season.

The host side made a lightning start in Turin as Luca Pellegrini thundered an effort against the crossbar before Bonucci marked his 35th birthday with the opening goal in the seventh minute.

Bottom side Venezia, who sacked its coach Paolo Zanetti in midweek, responded well, and went close to a first-half leveler, but Thomas Henry's header flew just wide.

The visiting side kept coming in the second half and got the equalizer it deserved when Mattia Aramu arrowed a strike into the net in the 71st minute, with the Juventus defenders arguing among themselves in the aftermath.

With Juve looking all out of ideas up front, it was left to Bonucci once more to prod home the winner from close range 14 minutes from time.

The victory helped Juve move to within a point of Napoli in third and crucially 10 clear of Lazio in fifth. Venezia stays bottom on 22 points, six adrift of the safety zone.

It has been a disappointing season overall for Juventus after coach Massimiliano Allegri returned to take over as manager for a second time.

Serie A's most successful team has struggled to keep pace with the league leader this term, sitting five points behind AC Milan ahead of the table-toppers' clash with Fiorentina on Sunday – something captain-for-the-day Bonucci regrets.

"When I wear the armband, something extra snaps to me," Bonucci told DAZN. "When I wore it this year, I always tried to be an example.

"When you take to the field in this shirt you are always aiming for the highest goals. We complicated our lives a little because three or four more points (this season) would be enough to be on top, but it will serve as a lesson for the future."