Leicester boss Claudio Ranieri is refusing to think about the Champions League knockout stages despite the Foxes' perfect start.
Islam Slimani's header gave the Foxes a 1-0 win over Porto and back-to-back victories in Group G to preserve their 100 per cent record.
The £29m forward has now scored six goals against Porto in 2016 to be labelled the 'Dragon Slayer' - Porto are nicknamed the Dragons - after his strikes for former club Sporting.
Leicester are top of the group ahead of FC Copenhagen, who beat Club Brugge 4-0, but Ranieri remained tight-lipped over their chances of qualification.
"I am superstitious, we have to stay calm, Copenhagen won 4-0 and they are very organised," he said. "For us now it's important to clean our mind and go back to the Premier League.
"It was important to win against Porto, because they are a very good team. They have quality players.
"I spoke a lot about making a clean sheet here. My players were very concentrated, they were strong, attentive in every situation.
"It was good for everyone after the bad defeat at Manchester United (a 4-1 defeat on Saturday)."
Slimani has now scored three goals in his first four Leicester games and, following his effort at the King Power Stadium, Ranieri said he had told the Algeria international and his team-mate Riyad Mahrez he expected them to produce.
"I was very confident with Slimani - because he often scored against Porto when he was a Sporting player," he said.
"I spoke with Riyad and Islam and said: 'Come on guys, let's make something special', and they made the pass and goal and it was good. After we defended very well and were very well organised."
Jesus Corona hit the post with eight minutes left as the Foxes were forced to ride out late pressure but deservedly took the victory following their opening 3-0 win at Club Brugge earlier this month.
Porto have not won in 17 games in England and were poor for long spells and only roused themselves in the final 20 minutes as Kasper Schmeichel saved from Hector Herrera and Corona hit the post.
They have one point from their opening two games and boss Nuno Espirito Santo knows they already face a battle to make it out of the group.
"Copenhagen won so we have no margin for error and this is a chance for us and we must go beyond our limits to do it," he said.
"It's not easy to come to the Premier League champions and start from the first minute like we finished. It's a challenge but I'm quite optimistic for the future."