Barcelona survived a scare as they came from behind to beat Linares Deportivo 2-1 in the Copa del Rey.
The third-tier side took a shock first-half lead at Linarejos through Hugo Diaz's header.
However, the gulf in quality eventually told after the break as Xavi's side turned the contest around with two goals in the space of five minutes.
Ousmane Dembele equalized when a long-range effort squeezed past Brimah Razak, before Ferran Jutgla's wonderful individual goal booked the visitors' place in the round of 16.
Dani Alves was handed his second Barcelona debut after finally being officially registered by the club.
The 38-year-old was immediately involved as his fifth-minute corner was headed narrowly wide by Ronald Araujo, while Ilias Chakkour was also off target from Nicolas Gonzalez's through-ball.
Despite their early pressure, Barca fell behind in the 19th minute as Fran Carnicer's superb deep cross was headed in by the well-placed Diaz.
The visitors enjoyed over 80 percent of possession during the first half, but could only register one shot on target from eight attempts courtesy of Gonzalez's ambitious long-range drive that Razak held.
Nevertheless, they got their equalizer in the 63rd minute as Dembele's long-range strike found a way past the Linares goalkeeper.
And moments after Lolo Guerrero's header was ruled out for offside at the other end, Jutgla completed the turnaround following a jinking run from the left flank.
Dembele then rattled the crossbar after a solo surge of his own, but the single-goal margin was enough to keep Barca on course for a sixth Copa del Rey triumph in eight years.