 On the first matchday of the 2009–10 Bundesliga, Diekmeier was voted into the "Starting XI of the Day" for "kicker"-magazine.Eight rounds into the competition, Diekmeier was the only Nürnberg player who had played eight full games, alongside goalkeeper Raphael Schäfer.In the final training session before the ninth match-round, however, he suffered a severe allergic reaction and was treated after an emergency helicopter flew in.