The Ivorian agreed a deal to move from CSKA Moscow last month and, having helped his country win the African showpiece, could debut against Parma on Sunday.
Garcia is confident Doumbia will prove a useful addition and thinks that the 27-year-old is ready to start.
"He had to go via Moscow and travel around a bit before coming here," Garcia explained on Saturday.
"We all know what sort of player he is - you only need take a look at his stats.
"He's a goalscorer, a striker who sticks them away for you. We expect a lot from him. Not that we're putting him under pressure; for now his only task is to settle into the team.
"He's ready to start and show what he can do."
Roma's bid to reel in leaders Juventus has stuttered of late - drawing four of their last five league outings to sit seven points off top spot.
Ahead of Sunday's visit from bottom side Parma, Garcia warned of taking Roberto Donadoni's men lightly.
"Three points is the only result open to us. Parma are a team that try to play football despite their position in the standings," he added.
"They went out of the Coppa Italia in the final minutes against the league leaders. For our part, all we can do is win the game and prove that there is a difference in quality between us.
"Our first aim is to win the next game, then we'll see after that. We have to focus on one game at a time, nothing else matters. All that matters is getting three points."
'Obviously Messi is the best player in history and being compared to him means that you're doing things right, but I try to be myself': Barcelona star responds to comparisons with Argentine legend
'Darwin Nunez would be gold for Arsenal': Liverpool legend claims Gunners should have signed Uruguayan striker in January
