Robert Lewandowski also scored twice in the 3-0 win on Tuesday.
Olmo said afterwards: "We're happy to win again and to add three points at a time, especially in front of our fans.
"Today's victory was important to stay at the top of the table. We were calm, we should have made the most of the spaces. We could have scored a few more goals, but we are happy to have achieved our objective.
"All of us who play up front can play in different positions, whether it's with Raphinha, Fermín or Gavi when he comes on, Pablo Torre... We are players who have that mobility. With Raphinha I have that 'feeling' to change positions and we don't have any problems."
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