Barcelona released a statement on their website that the Spaniard will be taking a short break after injuring his right thigh during the match.
Iniesta tangled with Hospitalet goalkeeper Carlos Craviotto after doubling his side's lead, which saw him substituted by Sergi Roberto in the 31st minute.
Nevertheless, the Catalans went on to complete the victory with goals pouring in by Thiago Alcantra, Issac Cuenca, Tello and Xavi.
Coach Pep Guardiola was full of praise for his team's hard work and serious attitude towards the game.
"We went for the ball, and never let our guard down," said Guardiola after the game, according to Marca.
"I did not want our team to slip up. We wanted to put the triumph in the cup [Club World Cup] behind us. We came from a long flight, and I asked my players to take the game seriously."
Barcelona will face Espanyol in La Liga on Jan. 8, next year, after taking a short rest during the winter break.