With Paulo Dybala not fully fit, Pirlo started new signing Alvaro Morata to partner Ronaldo up front.
Striker Issa Alekasir's header in the 88th minute found the back of net and sent the Reds to the competition's next round.
Flamengo had asked the Brazilian Football Confederation (CBF) to postpone the clash after reporting at least 16 positive coronavirus cases in their first-team squad, with only nine outfield players available.
Mexico will meet the Netherlands in Amsterdam on October 7 and Algeria in the Hague six days later.
Cherono will take on Ethiopians Birhanu Legese, holder of the third-fastest time of 2:02:48 in marathon history and Kinde Atanaw, the race defending champion and current record holder for the Valencian course in a race slated for December 6.
Tang Miao shot the opener in the 42nd minute for Chengdu and his teammate Wu Guichao slotted home with a curled volley in the 79th minute, sealing the game against Inner Mongolia 2-0.
Inter coach Antonio Conte started new arrival Aleksandar Kolarov but benched fellow summer signings Arturo Vidal and Achraf Hakimi, while Romelu Lukaku partnered Lautaro Martinez up front with Christian Eriksen behind them.
Luo, 20, defeated Billy Castle 3-1 and swept Jamie Wilson 3-0 before locking horn with world number five Mark Allen in his last group match. A draw was enough for the Chinese youngster to book a place in the second stage as the group winner.
Also on Saturday, Andre Villas-Boas' Marseille, still struggling for a win, was held by Metz 1-1 at home.
CHENGDU, China, Oct. 1 (Xinhua) -- It took Shandong just one quarter to seal their opening victory in the Women's Chinese Basketball Association (WCBA) league new season by overwhelming Daqing 101-51 here on Thursday.
TEHRAN, Sept. 29 (Xinhua) -- Ali Alipour, former Persepolis striker, has joined Portuguese team Maritimo, Tasnim news agency reported on Tuesday.