The winger was at his absolute best as Wales came from 1-0 down to win 2-1 in the World Cup qualifier at the Cardiff City Stadium.
He went close with a couple of efforts and created the best chance of the first half as Steve Morison headed his cross just wide, but Scotland led at the break thanks to James Morrison's strike.
Gareth continued to take the game to the Scots and was eventually rewarded in the 81st minute, when he was tripped in the box by Shaun Maloney and picked himself up to slot home the penalty.
Then, with a minute left, a moment of magic to win the game.
Picking up the ball 40 yards from goal, Gareth burst past Charlie Adam and let fly from 25 yards, his shot arrowing over Allan McGregor into the top corner.
It ended a run of five-successive defeats for Wales and lifted them above Scotland in World Cup qualifying Group A.
Wales boss Chris Coleman was full of praise. "Gareth keeps on producing swashbuckling performances and doing things that not many other players are capable of doing.
"He's a special player, we all know that, and if you think, he is 23 - he has not even peaked yet. He is an amazing player."