Senderos made his full international debut on 26 March 2005 in Switzerland's 0–0 draw against France in Paris. On his fifth cap, away to Cyprus on 7 September 2005, he scored his first international goal by opening a 3–1 win. On 12 November 2005, he opened the scoring in Switzerland's win over Turkey in the play-offs. After playing in Switzerland's successful qualifying campaign, he was named in their 2006 FIFA World Cup squad. He started alongside Patrick Müller in all three of Switzerland's group matches, and scored the first goal of the 2–0 win in the third match, against South Korea. He broke his nose and suffered shoulder ligament damage in the match, which ruled him out of the remainder of Switzerland's World Cup campaign.