The Netherlands international suffered an anterior cruciate ligament injury in last week's defeat to Napoli, and is certain to miss the remainder of the season, as well as the FIFA World Cup in Brazil.
Ahead of Monday's game with Udinese, Garcia called on his side to get back to winning ways as they look to cement a top-two finish and make certain of UEFA Champions League football in 2014-15.
"We want to do well for Kevin, as he deserves to play in the Champions League next season," the Frenchman said.
"In order to have a great season, you need to avoid too many injuries.
"Very few of our injuries were muscular, which means the work we did in fitness training was good, but you can’t do anything to protect against traumatic injuries during games."
Garcia welcomed the return of Francesco Totti to the side, saying it will give his side a greater threat going forward that they may have missed in Strootman's absence.
"I also now have more attacking options with Totti's return, so we needed some good news after a series of bad news moments," he said.
"We won't play with Totti the way we do with Mattia Destro or as we did with Marco Borriello. The team has to adapt.
"He's not like Gervinho either, someone who needs the ball played to feet into space.
"I have a choice to make on the left, as Alessio Romagnoli did very well, but now Dodo and Michel Bastos are also available."
