The Turin giants won 3-0 at Sassuolo on Sunday to clinch their eighth straight league victory.
The outcome coupled with Roma's 2-2 draw at AC Milan allowed the Bianconeri to extend their lead at the top of the standings to five points.
"We are getting extraordinary results," Juve coach Antonio Conte said. "We have won 14 and lost just one of our 16 league games this season.
"Now we have to turn our attention to the Coppa Italia, which is an important competition."
Not since the 1994-95 campaign, have Juve lifted the Coppa Italia.
Conte is set to ring the changes against Avellino in view of Sunday's match at Atalanta, Juve's last game of the year.
Marco Storari will replace Gianluigi Buffon in goal while attacking pair Fernando Llorente and Carlos Tevez, who struck a hat-trick at Sassuolo, will be rested in midweek.
Conte is set to field Sebastian Giovinco and Fabio Quagliarella in attack.
Avellino know they face an almost impossible task to surprise Juve in Turin.
"We are aware that we face the strongest team of all and we know it will not be easy," Avellino coach Massimo Rastelli said. "Juve are going through a fantastic run of form.
"But we have arrived to this point and we want to show the same determination that has allowed us to be fifth in the standings in Serie B.
"We know our strengths and our limits and we will give our all against Juventus."
The Campania outfit go into the match on the back Saturday's 1-1 draw at Trapani.
The outcome lifted Rastelli's side four points behind Serie B leaders Palermo.
Avellino beat Frosinone 2-1 earlier this month to continue their Coppa Italia adventure.
The winner of Wednesday's match will face Fiorentina in the quarter-finals of the competition.