Inter Milan moved up to fourth after crushing Reggina 6-0 at the San Siro stadium, continuing their revival under new coach Alberto Zaccheroni before Tuesday's Champions League game with Arsenal.
Modena caused Marcello Lippi's side some problems in the early stages with some aggressive play in midfield but they created little in the way of real chances.
Juve's Alessandro Del Piero might have done better in the 28th minute when he was put free by Nedved after a swift counter-attack.
But the Italy international striker's shot was pushed wide at the near post by Modena keeper Marco Ballotta, who minutes later did well again to keep out a fierce shot from Trezeguet.
But Frenchman Trezeguet did put Juve ahead three minutes before halftime with a controversial goal from a quickly taken free kick.
Five minutes after the restart Juve made it 2-0 when Nedved cut in from the left and beat Ballotta with a low right-foot shot from 25 metres.
The best opportunity for the home side came midway through the second half when former Juve striker Nicola Amoruso found himself in a good position but Gianluigi Buffon parried his shot.
"You could say that Modena were the better side in the first half. Even though they didn't create much they closed down and fought well," said Lippi.
The result puts Juventus on 26 points with AS Roma and Milan, who play on Sunday, on 21.
Juve face Inter next week at their Delle Alpi stadium and will have taken note of the Milan side's hammering of woeful Reggina with goals from six different players.
Defender Fabio Cannavaro opened the scoring with the best effort of the night -- a stunning 25-metre drive for the seventh Serie A goal of his career.
Two minutes before the break Nigerian teenager Obafemi Martins doubled the advantage with a brilliant individual goal, working his way past four defenders before firing into the bottom corner.
Martins then set up Dutchman Andy van der Meyde for the third in the 50th minute and 10 minutes later Spanish midfielder Francisco Farinos, who has won his place back under Zaccheroni, made it 4-0 after being put through by van der Meyde.
Argentine substitute Julio Ricardo Cruz added the fifth with virtually his first touch of the ball, rounding Reggina keeper Emanuele Belardi and slotting into the empty net.
Christian Vieri, who had been whistled by some Inter fans earlier in the game, completed the rout in the 75th minute.
