Copenhagen held on despite a dominant second-half showing from Porto to record a goalless draw in their Champions League Group G clash at Telia Parken.
Nuno's visitors remain second in the table -- two points better off than their opponents -- after leaders Leicester confirmed their qualification for the knockout stages with a victory over Club Brugge.
Serbia striker Andrija Pavlovic was unfortunate to see an effort blocked for the hosts in the opening stages after Rasmus Falk's headed pass before Porto then bossed possession for a short while.
Visiting midfielder Jesus Corona came close with two chances in a five-minute spell but lost the ball in an attempted break through the middle before his header then missed the target.
The home side began to find their feet midway through the first half but Maxi Pereira blocked Benjamin Verbic's close-range effort, while Peter Ankersen fired wide following a corner.
Ankersen forced a save from former Real Madrid goalkeeper Iker Casillas on the half-hour mark with a 25-yard shot.
Andre Silva, Ludwig Augustinsson and Erik Johansson were all thwarted for the home side as the half went on, while at the other end Atletico Madrid loanee Jota fired Otavio's cross over the bar as the score remained goalless at the break.
Corona came close again at the start of the second half but the Mexico winger's effort was blocked before Pereira sent Otavio's cross wide.
The Portuguese giants missed two chances in quick succession as Silva was denied by home keeper Robin Olsen as the game approached the hour mark.
Copenhagen were finding it hard to make an impact as the away side continued to dominate with defender Ivan Marcano's close-range header from Pereira's corner just missing.
With less than 15 minutes remaining, Alex Telles set up Portugal international Silva but he fired his long-range effort over the crossbar.
Teammate Jota sent his late effort the same way as Stale Solbakken's hosts held on for a share of the spoils.