Yacine Brahimi scored the only goal of the game to guide Porto to a 1-0 victory over Tondela in their Primeira Liga clash.
Both sides struggled in the early stages of the match to break into the final third as their passing games lacked cohesion, which limited opportunties.
Porto took the lead in the 28th minute through a stunning strike from Brahimi as he raided to the edge of the box before curling a left-footed strike over Claudio into the top corner.
Brahimi had the chance to double his side's advantage when he was played through the middle, but he could only put his strike wide of the post.
Andre Andre almost added a second when he weaved his way through the Tondela defence, but was denied just when he was about the pull the trigger by a well-timed challenge from Bruno Nascimento.
The visitors continued to threaten through Vincent Aboubakar, but he put his strike from close range past the post.
In the second half, Cristian Tello almost found a second goal for Porto when he raided down the flank and cut in onto his right foot, only to see his effort saved by Claudio.
Tondela were handed the chance to draw level when Maicon conceded a penalty with eight minutes to play, but Iker Casillas made a crucial stop to deny Salvador Perez from 12 yards.
Tello nearly secured the three points near full time, but he saw his late strike saved, although Porto managed to hold out to claim the narrow victory.
