Bremen 2–0 lost. After this, Mielitz remained on the substitute bench for the next two months until coming on as a late substitute following Wiese's sending off in a 3–1 loss against Bayern Munich on 29 January 2011. He appeared three more matches from 5 February 2011 to 19 February 2011 before Wiese's return from suspension. He remained on the substitute bench for the rest of the 2010–11 season. At the end of the season, during which he made the total of 10 appearances for the side, Mielitz signed another contract extension, keeping him until 2013. Ahead of the 2011–12 season, Mielitz was promoted to a second–choice goalkeeper behind Wiese, taking Vander's place and demoting him to third-choice. After starting the season on the substitute bench, he made his first appearance on 17 September 2011 coming on as a replacement for Wiese, who had been sent off in the early minutes of the match, and conceding a goal in the second–half from Philipp Wollscheid, in a 1–1 draw against 1. FC Nürnberg. While Wiese served a three-match ban until late October, Mielitz played the next three matches and filled in showing very good performances, including in a win over Hertha BSC on 25 September 2011. On 3 December 2011, he started again after Wiese was given a bereavement leave, and conceded four goals, in a 4–1 defeat to Bayern Munich. After suffering short–term injury in January 2012, he was featured in two matches between 17 March 2012 and 24 March 2012 following Wiese's injury. He remained on the substitute bench throughout the 2011–12 season and was limited to a total of 7 appearances for the side. Shortly after the end of the season, he signed another contract extension in May 2012 which would keep him until 2014. Ahead of the 2012–13 season, Mielitz was expected to be the club's first choice goalkeeper by the club's general manager Klaus Allofs following the departure of Wiese to Hoffenheim. In the LIGA total! Cup 2012, Mielitz was the hero when he made two saves in the penalties shoot-out (one from Bastian Schweinsteiger) in a 4–2 win over Bayern Munich to progress through the final which they beat Borussia Dortmund in a penalty shoot-out again the following day. After the match against Bayern Munich, he said YouTube helped him save a penalty from Schweinsteiger. After starting in goal in the opening game of the