However, his team were on top for most of the match and looked likely to equalise before Antonio Silva, who gave the ball away for the first goal, was harshly penalised for light contact with Luka Lochoshvili to give away the decisive penalty.
Regardless Portugal will face Slovenia on Monday and, saving any injuries, Martinez will have a mostly rested first XI to call upon.
History makers
Kvaratskhelia was the beneficiary of Silva sloppily giving away possession to Mikautadze, who after scoring in both of Georgia’s previous matches with Turkey and the Czech Republic turned provider.
Mikautadze gave a perfectly-weighted pass to Kvaratskhelia who burst through on goal from his preferred position in the inside-right channel and stroked home a precision finish.
It was unfamiliarly clinical finishing from Georgia who would have come into Wednesday’s match with more than one point had they made the most of their chances.
From there, Sagnol’s team were content to sit back and protect their slender lead as Portugal sent forward waves of attack against a packed defence.
First Ronaldo smashed a free-kick straight at Georgia goalkeeper Giorgi Mamardashvili in the 17th minute before he was booked just before the half-hour mark for dissent after what he thought was a foul from Lochoshvili.
Francisco Conceicao hit the side netting while Ronaldo protested to referee Sandro Scherer and moments later Joao Felix fizzed a long-range shot just wide.
Ronaldo’s frustrations continued almost immediately after half-time when looked certain to score from a corner only for Lasha Dvali to unwittingly save the day with his back.
Kvaratskhelia then wasted a great chance to double his team’s lead before Mikautadze, who has been Georgia’s best player in the tournament, stroked in his third goal in as many games from the penalty spot.
Georgia then closed ranks and made rare, but dangerous forays into Portugal’s defensive third, holding out for the win to the joy of their supporters.
© Agence France-Presse
Photo: Twitter @TheNapoliZone