[1] Although Farrell was successful in age-group interstate cricket, she did not make her senior debut for New South Wales until late in the 2006–07 season a month before turning 20.

Her state made the finals series, and in the first match she took 3/27 and was unbeaten on one as they took a one-wicket victory—the closest possible result in a winning run-chase.

New South Wales went on to claim the title, and Farrell was then selected for the national team to play New Zealand in the Rose Bowl series after only five matches—half a season of senior domestic cricket.

She took only eight wickets in the WNCL season and was dropped from the national team, missing three bilateral series for Australia before the start of the following summer.

Farrell transferred to Western Australia and while taking nine wickets, she also made 172 runs at a batting average of 34.40, a figure comparable to those of specialist batsmen, earning herself a recall to the Australian team.

During the bilateral series that followed against the hosts, Farrell made her Test debut, taking a total of 3/36, but she managed only one wicket in five ODIs.

Returning to Australia for the 2009–10, she had her most prolific WNCL campaign, scoring 171 runs and taking 18 wickets, including her first five-wicket haul.

Farrell played in the Rose Bowl series afterwards, and after taking one wicket in each of the five ODIs in Australia, was dropped for three fixtures in New Zealand.

[2] Farrell returned the following year and took 4/1 from three overs in the first match as New South Wales defeated Tasmania by ten wickets after dismissing them for 24.

[2] Despite the strong performances in her final year in age group state cricket, Farrell was unable to break into senior ranks until late in the 2006–07 season.

After taking 1/19 from her six overs, she came to the crease in the closing stages of the match as New South Wales' tail struggled to reach the target of 134.

Farrell retained her position in the team and was a key player in the first match, taking 3/27 from her ten overs as the hosts were dismissed for 136.

[2] During July in the Australian winter of 2007, a Rose Bowl series was held against New Zealand in the tropical northern city of Darwin.

Australia found the target difficult and won by three wickets and seal the series, sparing Farrell the need to bat on her debut.

Persistent rain forced the abandonment of the match and New South Wales retained their title on account of placing first in the round-robin phase.

[2] Farrell was dropped from the Australian team after these performances in the WNCL and missed the home series against England and the Rose Bowl in New Zealand at the end of the season.

In her first match for her new state, Farrell hit an unbeaten 29 to steer them to a four-wicket win over South Australia.

[2] Farrell was recalled to the Australian team for the Rose Bowl series in New Zealand in February and the 2009 World Cup held in New South Wales and Canberra the following month.

She was expensive in the next match, taking 1/35 from five overs in a heavy defeat, ending the series with 20 runs at 20.00 and four wickets at 15.25 and an economy rate of 4.69.

In the first Super Six match, Farrell took 1/30 from 10 overs and made 20 not out, attempting to engineer the end of the run-chase as Australia fell 16 runs short of India's 5/234.

The Australians hosted New Zealand for a three-match series in tropical Darwin at the beginning of June before the World Cup, and Farrell showed good form taking five wickets at 9.80 at an economy rate of only 4.45, with a best of 3/13 from four overs in the first match.

However, she was effective with the bat, scoring 13, 31 and 12, all unbeaten, against New Zealand, West Indies and South Africa respectively, the second innings coming when she was promoted up the order in an eight-wicket win.

[2] In her debut for Nottinghamshire in the one-day competition, Farrell scored 129, contributing more than 70% of her team's 179 as wickets fell around her regularly.

[2] The WNCL was expanded in 2009–10 with the addition of the ACT, so ten round-robin matches were scheduled, and Farrell played in all, scoring 171 runs at 17.10.

[2] Farrell had a successful time in the domestic T20s, now part of a full interstate tournament, scoring 99 runs at 19.80 and taking five wickets at 19.00 at an economy rate of 4.75.

Farrell played in all but the fourth T20 game, taking five wickets at 17.80 and an economy rate of 6.35 and she batted twice, scoring two runs at 2.00.

[7][8][9][10][11][12][13] In the first warm-up match, she bowled two overs late in the innings, taking 0/15, and did not bat as Australia lost to New Zealand by 18 runs.

[7] In the last warm-up match, she was again not required to bat and took 2/16 in a three-over spell at the start of the innings, removing Nain Abidi and Bismah Maroof as the Australians defeated Pakistan by 82 runs.

Her dismissal was part of a sudden collapse as Australia lost 6/16 including the last four wickets for four runs to be all out for 155 with three balls unused.

[10] In the final group match against the hosts, Farrell was promoted up the order came in at 4/78 in the 12th over with the intention of lifting the run rate, but made only 5 from 6 balls before being dismissed before Australia finished on 7/133.