Erling Haaland's double earned Manchester City a 2-0 win at FC Porto, giving Enzo Maresca his first Champions League victory as City head coach. But it was another match in which Maresca's side won without convincing.

City's main man up front was wasteful in the first half, with Diogo Costa making two saves from chances in the area and Haaland heading another good effort over the bar. Porto's goalkeeper was also brilliant, including stopping Rayan Cherki from the rebound of one of Haaland's chances.

Haaland made amends after just two minutes of the second period, nodding an Enzo Fernandez cross off the post after barging Jakub Kiwior aside. City then took their foot off the gas as Porto grew in confidence. Alan Varela curled just wide, while Gianluigi Donnarumma was nearly caught in possession by William Gomes.

Haaland tucked home Rayan Ait-Nouri's cutback in stoppage time to seal the result. City became the first team to beat Porto at the Estadio do Dragao this calendar year. But improvement is needed ahead of Sunday's Manchester derby at Old Trafford.