The Ghanaian arrived in Italy on Monday and signed a contract with the San Siro outfit until June 2015.
The 31-year-old opted to leave Stamford Bridge after seeing his first-team opportunities limited this season under Jose Mourinho.
"Essien is well but he has to grow in condition," AC Milan coach Clarence Seedorf said in Friday's press conference. "He will not start against Torino."
Milan have also bolstered their attacking line with the signing of Moroccan Adel Taarabt on loan from QPR.
"Adel is very motivated," Seedorf said. "He has a lot of character but before I make any judgements, I would like to get to know him."
The Rossoneri go into the encounter against Torino on the back of a 2-1 triumph at Cagliari, their second straight win, but must cope without their leading scorer Mario Balotelli, who is suspended.
Balotelli has scored nine goals in 16 league appearances to help Milan climb to ninth in the Serie A standings.
Seedorf believes his side have enough quality to beat Torino, even without one of their most influential players.
"I see a lot of willingness from my players," Seedorf said. "Everyone is rowing in the same direction.
"I believe we can have a good end to the campaign."
Giampaolo Pazzini will lead Milan's attack.
Torino have received positive news with Alessio Cerci having shaken off a back injury.
Cerci, who is Torino's leading scorer alongside Ciro Immobile with 10 goals, took a blow in last weekend's 1-0 triumph against Atalanta.
Tests on the Italian striker this week revealed no damage and the player has been given the all-clear.
Torino head into the encounter on the back of two straight league wins which have seen them climb to sixth place, just one point behind Inter Milan.
Coached by Giampiero Ventura, Torino have lost just one of their last nine games.