Kvaratskhelia is Georgia's star player, and he made the breakthrough in the clash with Roberto Martinez's side, collecting a pass from a certain Georges Mikautadze before firing into the bottom corner.
Mikautadze then proved to be the hero for Willy Sagnol's side, converting from the penalty spot to double Georgia's lead and give Portugal a mountain to climb.
Having dispatched his spot kick, Mikautadze became Euro 2024's leading goalscorer on three goals, moving him ahead of Germany duo Niclas Fullkrug and Jamal Musiala, Netherlands' Cody Gakpo, Romania's Razvan Marin and Slovakia's Ivan Schranz.
Next up for Georgia is a clash with Spain in the round of 16 on Sunday, and it is going to be incredibly difficult for the national side, who are competing in their first-ever major tournament, to progress any further.
Mikautadze is the leading goalscorer at Euro 2024
As a result, it may be difficult for Mikautadze to win the Golden Boot, although three goals were enough for Spain's Fernando Torres to finish as top goalscorer at Euro 2012.
At Euro 2020, Portugal's Cristiano Ronaldo and Czech Republic's Patrik Schick finished on five, while France's Antoine Griezmann was the top goalscorer at Euro 2016 with six.
Mikautadze has now made 28 appearances for Georgia, and he boasts an impressive scoring record of 13 goals, in addition to contributing two assists.
The 23-year-old spent time with Lyon during his youth career but moved to Metz in 2016, ultimately progressing to first-team level in 2019, and he has represented his current side on 64 occasions, boasting an impressive record of 38 goals and 13 assists in 64 appearances.
Mikautadze actually joined Ajax in August 2023, but he failed to score in nine appearances for the Dutch outfit and returned on loan to Metz at the start of January.
Clubs are competing to sign the Georgia star
The forward scored 13 times in 20 Ligue 1 appearances in the second half of last season, but he was unable to prevent Metz from being relegated from France's top flight.
Les Grenats have re-signed him on a permanent basis from Ajax this summer for €13m (£11m), but the Euro 2024 star is now expected to be sold for a profit, with a number of clubs thought to be interested.
L'Equipe have placed Monaco and Lens as contenders, but Football Insider have said that Newcastle United, Borussia Dortmund, Napoli, Lyon and Marseille are also keen.
Metz are allegedly looking for around €25m (£21m) for his signature, which could be a bargain considering his performances at this summer's European Championship.
Kvaratskhelia's own future at Napoli is also the subject of much speculation, but another Georgian star has made a serious impression this summer with three excellent displays.