Roma were beaten 3-0 by the defending Serie A champions in the first game after the mid-season break earlier this month, a result that moved Juve eight points clear of the capital club in the race for the Scudetto.
Garcia's men will have the chance to atone for that defeat on Tuesday at the Stadio Olimpico and Garcia, whose side defeated Livorno 3-0 on Saturday, insists that progression to the last four is the only thing on his mind.
"This is the most important game of this week," Garcia said.
"But above all it is a game that leads to the semi-finals, and that is what counts. We've to ensure that Roma is the team going through.
"The league? It is difficult to talk about this, as it is not my focus going into this game. The league is in the past and we are doing well. We moved two points (further) ahead of Napoli and three on Inter.
"We will have time to talk about this later, as there are still so many days ahead and we also have the return leg against Juventus at the Olimpico.
"We are solely concentrated on the Coppa and getting through to the next round."
Garcia has bolstered his squad with the signing of midfielder Radja Nainggolan - initially on loan with a view to a permanent move - from Cagliari, and is poised to make a further addition with the loan capture of Brazilian winger Michel Bastos from Al-Ain.
And the Frenchman is confident that the duo will improve his side.
"We are stronger now with these two players, as they give us more solutions," he added. "(Michael) Bradley may have left, but Nainggolan's arrival means that we have maintained numerical parity in midfield.
"Bastos provides us with more options going forward, especially on the flanks. With (left-back Federico) Balzaretti injured, he also presents us with a defensive option."
