Ousmane Dembele got some more minutes after coming on in the 58th for Lionel Messi against Celta Vigo in Barcelona's 5-0 win at Camp Nou.
Dembele did well in a bright display and ended up with an assist, as he curled in a corner which Rakitic emphatically headed home. It was the second goal he has created for a team-mate this season.
His entrance, along with that of Arnaiz, changed Barcelona's formation to 4-3-3. He combined brilliantly with the young forward when he chipped in a great through-ball which Arnaiz lashed into the side netting.