Such a star so far this season when wearing the sky blue of her English Women's Super League club Manchester City, Australia's most gifted young soccer talent again proved a frustratingly anonymous figure in the green and gold in Zurich on Friday night.
It once again raised familiar thorny questions about the 21-year-old. What's the most effective position in the national team to play Fowler? And when will a Matildas coach coax standout performances from the youngster, on a regular basis, that befit her gifts?
On Friday night, caretaker boss Tom Sermanni was the latest to wrestle with the Fowler conundrum, but didn't seem to get any nearer solving why she had again cut such a peripheral figure, just as she had done at the Olympics.
Nominally up front alongside the ever-busy Caitlin Foord in a 5-3-2 formation, Fowler roamed ever deeper searching for a playmaking role but just couldn't impact the game as the tigerish Swiss midfielders ensured she was starved of the ball.
She came off in the 78th minute, replaced by teenage prospect Daniela Galic, who was perhaps more conspicuous in her brief cameo.
Asked about Fowler's anonymity, though, Sermanni was quick to jump to her defence.
"She's a very talented footballer and and still a young footballer, so I don't want to sort of over-expose her in a sense," said the Scot.
"It was a game that was difficult, for not just Mary, but difficult for our midfield players, because Switzerland defended very well, defended very deep.
"They had lots of numbers in midfield, and it made it difficult for us to get some quality possession in there. It's a case of coming back, looking over it and seeing how we can solve that problem, to get our key players on the ball more often."
Interim coach Tom Sermanni backed Fowler, saying the Swiss made it difficult for others too. (Brendon Ratnayake/AAP PHOTOS)
"Sometimes you've got to give credit to the opposition and what they did. For part of the time in our midfield, we didn't quite work out how to press or when to press, and the result was that Mary never really got a foothold in the game at any time.
"But I also thought that a lot of our play actually went down the left hand side, and that didn't allow her to get on the game and to start dictating the game."
Now that her Man City teammates have got in sync with her abilities, Fowler has been strikingly good for them as a winger or even when filling in as the central spearhead in the absence of their superstar attacker Khadija Shaw, but she's not gelling in the national set-up in the same way.
Monday night in Duisburg will be another acid test when the Matildas face a German side, ranked four in the world, who hammered them at the Games, who are fresh from beating England at Wembley and who will be determined to give a winning send-off to their Olympic-winning heroine Alexandra Popp.
"We certainly need to step up based on tonight's performance," conceded Sermanni.
"But it was the first game the team have played for a while, and the Germany game will be entirely different.
"I think Germany will come out to play more open, more attacking football, and it might be a little bit more open, which makes it a little bit more dangerous for us defensively but it also may give us more opportunities attacking-wise."
