On 10 July 2016, it was announced that Castán would be loaned to Sampdoria for the 2016–17 season. However, on 18 August, just two days prior to the start of the new season, Sampdoria confirmed that the loan had been terminated and that the player had joined Torino on loan instead. Castán featured in 3 out of 5 of the "blucerchiati's" pre-season matches, including their 3–2 away defeat against FC Barcelona in the Joan Gamper Trophy.