Espanyol made the perfect start when Roberto found the net in the third minute, before the forward doubled the visitors' advantage 14 minutes later.
Osasuna dominated possession for long periods but struggled to turn their territorial advantage into goals as Espanyol defended resolutely to claim all three points.
Roberto strikes early
Espanyol needed only three minutes to break the deadlock.
Marcos Fernández provided the assist as Roberto Fernández finished the move to put the visitors 1–0 ahead.
Osasuna attempted to respond, but Espanyol remained dangerous on the counter and doubled their advantage in the 17th minute.
This time, Omar El Hilali supplied the assist for Roberto, who calmly finished to complete his brace and give the Catalan side a commanding lead before the midway point of the first half.
• Osasuna: No goals
• Espanyol: Roberto Fernández 3', 17'
Osasuna push for a response
Osasuna enjoyed the majority of possession, finishing the match with around 61 per cent, compared with Espanyol's 39 per cent.
The home side also registered more total passes and spent long periods around the Espanyol penalty area, but the visitors' defensive organisation prevented Osasuna from finding a way back into the contest.
Osasuna thought they had pulled one back when Rubén García found the net, but the goal was ruled out following a VAR review.
The hosts continued searching for a breakthrough after the interval, but Espanyol's backline remained disciplined.
Espanyol withstand pressure
Espanyol's goalkeeper Marko Dmitrović and the defence dealt effectively with Osasuna's attempts to reduce the deficit.
The visitors were also able to threaten when space opened up, although the second half produced no further goals.
Osasuna finished with four shots on target, while Espanyol managed three. The visitors' efficiency in front of goal ultimately proved decisive, with Roberto's two early finishes giving them a cushion they never surrendered.
Roberto continues impressive scoring form
The victory was particularly significant for Roberto Fernández, who has now scored five goals this season, according to coach Manolo González.
The Espanyol manager praised the striker's contribution after the match while also highlighting the team's overall performance in what he described as a difficult away fixture.
The result also ended Espanyol's three-match run without a victory and strengthened their position in the early LaLiga table.
Espanyol moved to seven points from five matches, while Osasuna remained on seven points after suffering their second consecutive defeat.
Match details
• Osasuna: No goals
• Espanyol: Roberto Fernández 3', 17'
Venue: El Sadar, Pamplona
Competition: LaLiga
Date: 12 September 2026
Result: Osasuna 0–2 Espanyol