But never fear, bowlers of New Zealand, the attentive groundsman was there straight away to patch up the puncture wound.
Mac, who grew up on a farm in Tokanui in Southland, has been writing and playing music since she was six. She was nine when she won her first of three Gore Golden Guitar awards; at 15 she won the Play It Strange songwriting competition with her song Blue Butterfly; and at 16 she took out the Smokefree Rockquest female musician award.
She also got the chance to go to Nashville when she was 17 to sharpen up her songwriting skills: "Amazing city. So inspiring."
But with Girl In Stilettos, from her debut album Little Stranger released late last year, she is making a name for herself in the mainstream.
"It's close to knocking Flo Rida off," she beams. She's right, although it's failed to beat the American rappers Wild Ones to the top spot just yet. Still, it's been nestled in the top three for the past four weeks.
While her roots lie in country music, Girl In Stilettos has a lovely, plodding lope to it, with hand claps gently nudging it along too, and Mac's innocent yet somehow cutting lines like "I don't really miss the 1950's fishermen trying to chat me up outside" and "it's like they all just wanna do me".
"What people like about the song I think is that it's so honest," she says. "And people, especially women who have had sleazy 50-year-old men hitting on them, relate to it," she continues with a laugh.
While she exudes a sultry, slightly pouty, confidence in the video, in person the 20-year-old is shy and often looks away when she's talking so as not to catch your eye.
"I can be shy. I'm certainly not quite as confident in my real life as my lyrics. It's very easy for me to be open when I write songs."
But then she has flashes of being matter-of-fact and determined. "It feels like it's the right time for me," she says of Girl In Stilettos' rise to the top of the pops.
That song is about her moving to the "big smoke" from the country - hence the contrast of powerlines and pohutukawa trees, and characters such as the fishermen and the Auckland "asshole".
But this country girl has taken to the big city with relish. She went a little wild when she got to Auckland getting a whole bunch of piercings, much to her dad's dislike. She took them out before shooting the video for Focus - a song written for her dad - and the majority of them have stayed out since.
Then again, she's still just as handy with a drench gun as she is with a hair dryer.
"I certainly wouldn't be wearing Karen Walker and high heels when I'm with dad out drenching," she laughs. "Yes, [moving] has changed me but I go back and in a heartbeat I would help out with lambing ... and I'm still a bit clumsy but it doesn't take me too long to get back into it."
She admits the album, the majority of which was recorded at Neil Finn's Roundhead Studios with Sweden-based American producer Brady Blade (who did Brooke Fraser's debut What To Do With Daylight), took a while to record.
"It hasn't been easy, but it's been extremely rewarding," she resolves.
It is made up of many songs from her school days, that focus on her growing up and finding yourself with Same Cartoons about "that boy at primary school who threw rocks at you", and Focus is about her being a "little rascal".
She also admits the album was a purge of songs - and it feels good to have them out there, finally.
"Even though they were written a long time ago I really wanted those songs to be heard, I'm really proud of those songs and my family are really proud of them."
She is full of praise for her family, friends, and her manager (Haddon Smith, who is also in her band), as well as her hometown.
"I did a sort of a little album launch back [home] and it's like it's their success as well. It's not just for me, it's for everyone down there, they are such a big part of it too, because they've been coming out to see me since I six years old. I'm quite loyal."
She plans on "working" Little Stranger more this year with a nationwide tour but she's also constantly writing new material with some of her new songs taking on a bluesy country bent.
"I love writing country music, but then I love writing R&B and pop. But I'm still discovering my songwriting. Sorry that's a bit vague isn't it? I just love music really."
LOWDOWN
Who: Annah Mac
Listen to: Little Stranger, out now
Playing: Classic Hits Winery Tour, Vilagrad Winery, Hamilton, March 2, Villa Maria Estate, Auckland, March 3. Also at Waiheke Jazz Festival, April 6.
-TimeOut
