Porto remain two points off the top of the Primeira Liga, as they warmed up for Thursday's trip to Ibrox with a 1-0 win over bottom side Aves.
Sergio Conceicao's side face Rangers in the Europa League this week after a 1-1 draw in Portugal in the previous round of fixtures.
Porto head into that match following a 1-0 win over the bottom side in the Portuguese top flight, but the result was more comfortable than the scoreline would suggest.
With Benfica beating Rio Ave last night, their rivals knew they had to win to keep touch at the top.
After nine minutes the Estadio do Dragao rose in a minute's applause for club legend Fernando Gomes, who is battling cancer.
Ivan Marcano put the hosts ahead four minutes later.
Otávio sent in a cross from the right which went very deep, and the Spaniard arrived late at the back post to volley home with his left foot.
Bruno Costa thought he'd won a penalty after going down under Afonso Figueiredo's challenge, but referee Hélder Malheiro changed his mind after reviewing the incident on the VAR monitor.
Luis Diaz drew a great save from the Aves goalkeeper, who also tipped Pepe's header onto the bar in the second half.
The post denied Soares a deflected goal and Aves, who brought on Zinedine Zidane's son Enzo, escaped with just a 1-0 defeat.
