After a goalless opening half, Ronaldo opened the scoring five minutes after the restart with a bullet header following a short corner. It was the Real Madrid forward’s ninth goal in the European Championships, equalling Michel Platini’s all-time record.
Three minutes later and Ronaldo was again at the heart of things as his shot-cum-cross was turned in by Nani, who had managed to stay in an onside position on the penalty spot to make it 2-0, and that's it how it stayed.
As expected, the match started at a cautious tempo, with both sides seemingly wary of making any errors in the opening exchanges.
Apart from Hal Robson-Kanu's hand ball just three minutes in there was no noteworthy action to speak of in the opening ten minutes of play.
The first shot on goal eventually came in the 16th minute, João Mário bursting through on goal before dragging a driven effort wide of the left-hand post from wide on the right.
The attempt on goal sparked an almost immediate reaction from Wales, who went agonisingly close to breaking the deadlock three minutes later. In a move reminiscent of training ground drill, Gareth Bale slipped his marker before firing over from Joe Ledley's corner kick into the danger area.
Bale again went close to finding the opener on 22 minutes following a trademark surging run from inside his own half. The Real Madrid sprang clear of three opposition players before letting fly from all of 25 yards, only for his effort to fly straight into the grateful arms of Portugal keeper Rui Patricio.
Portugal's rearguard were again called into action just three minutes later, but Andy King saw his header deflected over the bar by centre-back Jose Fonte.
Having soaked up the pressure, though, Portugal ended the first half in the ascendancy. However, they were unable to make their chances count as Cédric Soares, Adrien Silva and star man Cristiano Ronaldo all failed to find the mark.
While it's fair to say the first half was a lacklustre affair, the same cannot be said of the second stanza.
The match sprang to life just five minutes in as Cristiano Ronaldo rose above his marker to power home a bullet of a header from Raphael Guerreiro's pin-point corner kick.
Wales were still struggling to come to terms with the opening goal when Portugal struck against just three minutes later. Ronaldo turned provider for the second goal, firing a scuffed shot at goal which was slotted into the back of the net by Nani, who leaped to divert the ball past a wrong-footed Wayne Hennessey in the Welsh goal.
Wales' players were left shell-shocked by what they had witnessed and they never fully managed to recover.
Portugal, meanwhile, showed no signs of letting up as they looked to land the knockout blow. Ronaldo fires just inches over the crossbar with a dipping free-kick on 63 minutes before Nani saw his swerving shot from range palmed into the danger area, only for Mário to inexplicably fire wide on the follow-up.
They continued to apply the pressure, with Jose Fonte heading straight at Hennessey in the 70 minute, and Renato Sanches lashing a powerful effort over the goal three minutes later.
Wales eventually managed to lodge their first second-half effort on goal in the 75th minute, Bale firing straight at Patricio with a speculative effort from 30 yards out.
Portugal were never under any real threat, though, despite Wales piling men forward in a bid to reduce the deficit.
In fact, Portugal looked most likely to find the net in the closing stages of the game, Danilo Pereira seeing his goal-bound attempt snapped up at the second attempt by Hennessey, before Ronaldo shot just wide from a tight angle out on the right-hand side of the box.
And that was the last shot on goal as Portugal shut up shop in the remaining minutes to secure a 2-0 victory and a place in the 2016 European Championship final at Stade de France on Sunday.
Portugal: Patricio, Cedric, Jose Fonte, Bruno Alves, Guerreiro, Danilo, Joao Mario, Adrien (Moutinho 79'), Renato Sanches (Gomes 74'), Nani (Quaresema 86'), Ronaldo
Wales: Hennessey, Gunter, Chester, Collins (Williams 66'), Williams, Taylor, King, Ledley (Vokes 58'), Allen, Bale, Robson-Kanu (Church 63')