Matthewson admits he always fancied fellow New Zealander Warren Gatland and co to head home with a first series win since 1997 and he sees no reason to change his mind after his side shipped nine tries in yesterday's encounter.
"Prior to the game, I thought the British & Irish Lions were going to come in and deal to the Wallabies," said Matthewson.
"I'm still thinking The Lions will win 2-1. They played a good style.
"Guys like George North are big guys. You've got guys like Jamie Roberts (to come in), and then Brian O'Driscoll is just so skilful, and then there's Halfpenny as well, and Sean Maitland - a Kiwi boy!
"They've got all the tools to play an attacking game and they can muscle up up front as well.
"It's going to be a good series but I'm going for The Lions."
George North caught Alby Matthewson's eye with a strong showing on his first Lions start
Matthewson was particularly taken by The Lions' willingness to attack out wide and put the ball through the hands, something that many of the locals had failed to anticipate.
More than half of the tourists' tries came from the backline, while three of the forward efforts were scored just inches inside the touchline.
"It was a really fast game. The conditions were great for running rugby and it was great to see The Lions play with a fair bit of width. They used their big wingers and played an expansive style," added Matthewson.
"They identified the space really well. We were expecting a fair bit of play off nine as the week before that's what they did. We targeted around that area but they played off 10 a wee bit more and exposed us there.
"They used the width really well and we over defended in close at times because that's where we were expecting them. We got caught short out wide a couple of times and they put us away. Full credit to them, that's what quality teams do, and that's what they did.
"In the step up from club rugby to Super level, you get punished for your mistakes. At international level, you get punished every single time."
The Lions scored the majority of their nine tries out wide during an exciting display at Patersons Stadium
There was one area that will need to be addressed quickly, though, according to Matthewson.
The former Hurricanes halfback was a little surprised by how much success his side had around the fringes and has warned The Lions that any such weaknesses will be eagerly sniffed out by a Wallaby side driven so effectively by fellow No9 Will Genia.
"The northern hemisphere teams are known for their strength up front over here and I'm sure they'll address that as we got some good pay out of keeping it in tight and working around the fringes.
"We tried to play as an eight up front and that was working so we stuck to that. We identified that they were using a kind of blitz shut defence: they close the gate from the outside, so we weren't really going to shift it wide unless we had really quick ball.
"I thought that their D a wee bit wider out around the fringes was alright, but once we started going through the middle and around the sides we got good gains. There were a few soft yards there.
"I know that their final team hasn't been decided but they're going to need to sort that stuff out up front because the Wallabies are obviously going to look at that as Genia's their lynchpin. It was the quick pick and goes and getting lower than them in cleaning out, but I'm sure they can fix that."