Nagelsmann, whose sacking in March 2023 led to Tuchel's arrival, was tipped to return to Bayern, but has now extended his contract with Germany until 2026
Real's expensively assembled squad, including FIFA Ballon d'Or winner Cristiano Ronaldo and Gareth Bale, the world's most expensive player, could not find a way past Gijon's determined defence at the Molinon.
Champions Barca earlier secured a hard-fought 1-0 victory at Athletic Bilbao in their opening match of the campaign, with the game settled by a fine Luis Suarez volley in the 54th minute after Lionel Messi had a penalty saved in the first half.