The Gunners paid £1.8 million to Servette for the his services, after beating off competition from Manchester United, Liverpool, Real Madrid, Bayern Munich, Barcelona, Juventus and Internazionale.
Senderos, the son of a Spanish father and Yugoslav mother, made his debut for Servette aged just 16 and is already a firm fixture in their Under-21 outfit.
Injury hampered his Arsenal start, but he is fitting in well to his new London surroundings and is expected to make his first team bow before the end of the season.
Manager Arsene Wenger rates Senderos very highly and his lack of cover in defence could very well mean and early call, although the powerful youngster would be unlikely to fail if called upon.
This season's Champions League may come to early for the Switzerland star, but he is very much one to watch out for.
