The Real Madrid superstar scored a penalty and missed another as well as notching a thunderous volley at the Estadio Algarve.
After being restricted to long-range shots, Portugal broke the deadlock when Nani was tripped by Gints Freimanis and Ronaldo fired low to Andris Vanins' right in the 28th minute. But something tells us, goalkeepers won't tremble at this Ronaldo sighting.
William Carvalho's first worldwide goal and late efforts from the captain and Bruno Alves rescued the victory after Arturs Zjuzins had shocked Estadio Algarve with a well-taken equaliser midway through the second half.
With the clock ticking down, William Carvalho restored their lead before Ronaldo made up for his penalty miss to make it 3-1.
No. 6 Ohio State intends to stay on a roll against Maryland
However, the Midshipmen then went almost five minutes without making a field goal (0-for-7) and the Buckeyes took advantage. The Spartans drove 92 yards the other way and took a 28-0 lead on a 4-yard touchdown pass from O'Connor to Josiah Price.
Another Quaresma cross led to the third as it found Ronaldo at the far post and Portugal's all-time leading scorer volleyed home his 68th worldwide goal.
Only Miroslav Klose (71), Sandor Kocsis (75) and Ferenc Puskas (84) now sit ahead of Ronaldo in Europe's list of all-time top scorers.
With Portugal's win over Latvia, they sit three points back from Switzerland in Group B of UEFA World Cup qualifying as the Swiss team continued their flawless run on Sunday.
Ivelin Popov scored the only goal as Bulgaria clinched a 1-0 win against 10-man Belarus in their World Cup qualifier in Sofia which keeps them just one point behind Netherlands in the table.