Forwards
Left Forward: Douglas Costa
After making his loan move from Bayern Munich permanent this summer, Costa will be expected to retain his place in Allegri's starting XI.
The Brazilian's excellent dribbling ability makes him a perfect foil to the fox in the box striker that Ronaldo has transformed into over the last few years.
Costa will also be licking his lips at the opportunity to link up with one of the greatest goal scorers in the game, who will help him in both improving his assist stats by freeing up space for him in the box.
Right Forward: Paulo Dybala
For the first time in his Juventus career, Paulo Dybala will not be the focus of the Italian media. For years the Argentine has been touted as the next big thing, but after a hugely disappointing World Cup campaign where he could not break into a weak Argentina starting XI, he must be raring to get back on the pitch and show the world his ability.
It will be interesting to see how he will react to playing second fiddle to Ronaldo. Either he will enjoy the reduced pressure as a result of the attention that Ronaldo will garner or he will crave for the spotlight like Neymar did while playing with Messi before forcing through a move to Paris Saint-Germain last summer in order to become the face of his club.
Centre Forward: Cristiano Ronaldo
Cristiano Ronaldo will finally officially play the role that he has been secretly playing for Real Madrid for a number of years now.
While a left winger on paper all his career, in truth Ronaldo has been playing in a more advanced role than Karim Benzema for the past several seasons and now the departure of Gonzalo Higuain from Juventus it is clear that the Portuguese legend will be featured in a central role under Allegri.
It is only a tribute to the quality of Ronaldo that even at the age of thirty-three he can command a €120 million transfer fee and turn a team into instant Champions League contenders.
It will be interesting to see, though, how Ronaldo will adjust to a new club at such an advanced stage in his career. He will also miss playing each with creative forces like Luka Modric and Toni Kroos.
However, if there's one thing that we have learned about the Portuguese talisman in all his years at the peak, it is that whatever he does is guaranteed to be must-watch.