Cristiano Ronaldo scored with eight minutes of normal time remaining to earn Portugal a 1-0 victory over Sweden in the first leg of their World Cup qualifying playoff in Lisbon.

The visitors seemed content to take a goalless draw back to Stockholm for Tuesday's second leg, but the Real Madrid forward struck late on to establish Portugal an advantage and steal the show from fellow Ballon d'Or nominee Zlatan Ibrahimovic.

Sweden looked for an away goal in the first period and it was their captain who was nearly the architect, when his dummy allowed Sebastian Larsson to take on a shot which was well saved by Rui Patricio.

Kim Kallstrom seemed to have Patricio beaten minutes later with a free kick which curled just wide of the post, but another set piece effort from Sunderland winger Larsson later in the half was way off target.

Sweden's approach seemed to change after the interval, though, and Portugal pinned them back in their own half with a period of attacking pressure which yielded two chances for Helder Postiga.

The Valencia striker's 54th-minute shot was denied by Andreas Isaksson, who had earlier saved well from Joao Moutinho, and then headed just high of the crossbar from Nani's corner 10 minutes later.

It took Portugal until the 82nd minute to break the deadlock when Ronaldo met a cross from Miguel Veloso and sent the Estadio da Luz wild with a thumping header that left Isaksson helpless.

The same combination nearly doubled Portugal's lead, as Ronaldo struck the crossbar with an almost identical effort in the final stages, but Sweden hung on to keep the second-leg deficit to just one goal.