The German international picked up the issue towards the end of Chelsea's pre-season preparations and has endured a frustrating start to the campaign, only making his debut as a substitute in the midweek League Cup thrashing of Wolves.
"It was a hard time doing the whole pre-season and then the US tour, then the injury, but it's football and it happens, now I'm happy to be back," the 23-year-old told the Blues' official website.
"Of course it's not nice, for any player, there is never a good situation to be injured but now I feel good and can forget that time, it's in the past and I look to the future.
"I have no targets, of course I want to play as much as possible and now I am nearly 100 per cent fit again, it makes me happy and I want to play. The injury is done."
|11/2||Lukas Podolski is 11/2 with Bet365 to open the scoring when Arsenal take on Chelsea on Saturday
The former Werder Bremen player turned his attention to Saturday's clash with Arsenal, and the 23-year-old is expecting an entertaining tie between two attacking teams.
"Last year to this year we changed a lot, now we have more creative and offensive players and I hope we can help the success like last year," Marin explained.
"Arsenal have a good team of course but they lost Robin van Persie, who was the best scorer last year, and is at the top again, so it is interesting to see how they do."One of Van Persie's replacements is Marin's compatriot Lukas Podolski, who is starting to hit the form that has seen him earn more than 100 international caps.
"At the beginning it was a bit new for him but now he is doing very well and has scored a few goals," Marin said of Podolski.
"I haven't talked to him. We know each other from the national team but we are not really friends, I talk more with Per Mertesacker because we played together at Bremen.
"There are two German players to play against and I hope I am with the team. The important thing is to win and keep our position in the Premier League.
"We have a very good defence, so it will be very hard for Lukas to play against us.
"I'm not sure they have played against a team so good so it will be harder for him and I know Branislav Ivanovic very well, he is one of the best defenders in the world so I am not scared."