Chiesa, a second-half substitute in Friday's (AEDT) clash at the Allianz Stadium, curled in off the post with 12 minutes remaining.

Moise Kean had given Juve an early lead but his effort was cancelled out by Mattia Valoti.

Kean saw what he thought would be a winner disallowed for offside, but Chiesa struck just after to settle the tie.

Nicolo Fagioli spurned a glorious chance for Juve in the opening moments but that miss mattered little as Kean headed Weston McKennie's cross into the far corner in the eighth minute.

Against the run of play, Valoti struck his third goal in as many Coppa Italia rounds to restore parity – Mattia Perin only able to push the forward's header into the roof of the net.

Juve's youngsters responded well, Samuel Iling-Junior firing wide and Matias Soule forcing a diving save from Cragno, but the host could not retake the lead before the break.

Kean came close to a second four minutes after the restart, bounding forward into the area, though Cragno was again on hand for Monza.

Juve had the ball in the back of the net after Danilo's shot deflected off Pablo Mari and against the crossbar, with Kean heading the rebound home, only for the offside flag to cut his celebrations short. 

The pressure finally told in the 78th minute, with Chiesa finding room down the left-hand side of the box and curling an effort in off the right-hand post.