The equation was simple: if Weston-Webb progressed, Hareb would be promoted to the Championship Tour (CT). If Callaghan progressed then she would be making the step up, leaving Hareb to consider her future.
"Three years on the QS, where you might be lucky to break even if you win an event. Other than that you're pretty much travelling and even if you win you're losing money, which you can only do for so long," the 27-year-old from Taranaki explains.
"That was my third year of doing that and I was definitely digging deep into my funds and using my credit card a lot so I would have definitely had to have a big think about doing it next year for sure."
But the Hawaiian won, and the Kiwi was back.
Hareb was the first New Zealand woman to reach the World Tour, realising her dream at the young age of 17 on her first attempt at qualification in 2008.
She remained there for six years before losing her spot and then faced the reality of just how hard it is to secure a spot on the biggest stage in the sport.
"When I first got on I was pretty young – 17 when I qualified – and I did it the first year I tried, so I guess it all just went kind of quickly and I guess easily in retrospect compared to these past three years.
"I definitely appreciate this one a lot more than the first time around."
On the 2015 and 2016 qualifying series, Hareb was in the race for the six promotion spots all season, but fell one big result short both times.
In 2015, she missed qualification by just three places, while the following year she missed out by five.
"Wanting it more than ever and getting within a couple of spots of requalifying was pretty devastating at the end of the year, and just finding the sponsorship and funding to just get from event to event.
"Having to worry about if you do have enough money for the next event, or that year puts more pressure on you to do well and get through more rounds, obviously to make more prize money and rely on your prize money. It's a bit of a double-edged sword – it can give you motivation but it can definitely put a lot of stress on you as well."
Funding stresses have followed Hareb throughout the majority of her career. She was dropped by her main sponsor, Billabong, in 2011 not long after she had turned down another sponsorship offer to remain loyal, and self-funded her World Tour campaigns in 2012 and 2013.
Hareb will be one of only two new faces on the CT next year, alongside American teenage sensation Caroline Marks who, at 15 years old, is the youngest to ever qualify for the women's tour.
When Hareb first qualified, Marks was 6. But after what have been a tough three years, Hareb says she's relishing the opportunity to get back to competing at the top level in a year that shapes up to be one of the most exciting in recent times.
On the 2018 CT, women will compete at famous South African break Jeffrey's Bay as well as at Kelly Slater's artificial wave.
With Hareb being the only athlete on next year's tour who hasn't had a chance to try out the "perfect wave" yet, she was eager to get the opportunity.
"They want to try to get me there before the actual event so it's fair and they can say we've all had a practise there."
And while she faced her mental struggles to try and get back with the best, the reward was worth it.
"When you keep losing year after year you definitely get down on it all, but third time lucky – I came back."
