At the start of the 2010–11 season, Tiendalli started in the Johan Cruyff Shield match against Ajax and helped Twente win 1–0. He was then involved in four consecutive clean sheets in the first four league matches of the season. He made his UEFA Champions League debut against Inter Milan on 14 September 2010, in the starting eleven, as FC Twente drew 2–2. He went on to make two more appearances in the Champions League, but Twente finished in third place in the group stage, relegating the club to the UEFA Europa League. The club advanced through the knockout stage to the quarter-final, in the first leg of which Tiendalli received a straight red card in a 3–1 loss against Villarreal. Twente ultimately lost the two-legged tie 8–2 on aggregate. In the 2010–11 season, he lost his first-team place because of injuries and competition from other players. Tiendalli finished the season having made twenty-eight appearances in all competitions. At the end of the season, it was announced that his contract would not be renewed after talks stalled. A week before his contract expiry, he attended the club's first session of the new season, insisting it was to maintain his fitness. However, Michel Preud'homme's successor as manager, Co Adriaanse, offered him a new one-year contract, which Tiendalli accepted. After signing the deal, Tiendalli stated that he hoped to make a fresh start under Adriaanse.