Bright sunshine greeted the teams in Pamplona, and the match began with both sides looking to set an early rhythm at El Sadar.
It was the hosts who struck first as Roberto Torres was left unmarked to volley in at the back post on six minutes, and a boisterous home crowd got behind their team who made life difficult for the visitors in the opening quarter hour.
Chances were few and far between, due in no small part to the game being played largely in a congested midfield. Barça looked to play it wide at every opportunity, with Jordi Alba, on the occasion of his 200th league game for the club, more involved as the half wore on.
Barça continued on the front foot, working to prise open the gaps in a well-organised Osasuna back four who held firm until the break.
At half-time, Ernesto Valverde made his first change, bringing on 16-year-old Ansu Fati and replacing Nélson Semedo. Within five minutes, the youngster had levelled the scores, and in so doing had become Barça’s youngest ever goalscorer in La Liga.
As the hosts began to tire, the blaugrana began to find the spaces they hadn’t in the first half, and Arthur soon put them in the lead with his first official goal for the club (1-2, min 63).
With nine minutes to play, Gerard Piqué fell foul of the new handball rule and was adjudged to have handled, Roberto Torres equalising from the spot (min 81, 2-2).
Carles Pérez, who’d provided both assists, went close himself towards the end of the 90 minutes, but in the end, the points were shared.