Barcelona missed out on becoming the first side to reach the Champions League knockout stages as they were stunned by Shakhtar Donetsk.
Danylo Sikan scored the game’s only goal, meeting Giorgi Gocholeishvili’s cross with a looping header.
Newerton thought he had added a late second, but the teenager’s effort was ruled out for offside.
Barcelona needed a point in Hamburg to advance from Group H with two matches to spare, but they were made to wait.
Despite dominating possession, the visitors were unable to break down the Ukrainian champions.
However, Xavi’s side remain top of Group H with 10 points and will reach the knockout stages if they avoid defeat to Porto in their next match on 28 November.
Shakhtar, who last beat the five-time Champions League winners Barcelona in 2008, are third in Group H with six points.
Marino Pusic’s team are hoping to reach the knockout stages for the first time since the 2017-18 campaign, when they lost in the round of 16 to Roma.