In May 2022 Nitschke became the interim head coach of the Australian women's team[2] and was appointed full-time on a four-year contract in September 2022.

[3] Nitschke made her senior debut in the Women's National Cricket League (WNCL) for South Australia at the relatively old age of 24 in 2000–01.

During the 2004–05 WNCL season, Nitschke scored 144 runs at 36.00 and took ten wickets at 17.50 and was rewarded with selection in the Australian team for a One Day International (ODI) series in India.

At the end of the 2006–07 season, the Australians played in a quadrangular tournament in Chennai and Nitschke batted in the upper-order for the first time, making 200 runs at 28.57 and top-scoring with 81, hermaiden ODI half-century, as Australia defeated New Zealand in the final.

Her best performance was an 87 and 3/43 in a group match against South Africa as Australia eventually came fourth after losing the third-place playoff to India.

In the inaugural Women's World Twenty20 in England in 2009, Nitschke made 130 runs at 32.50 and took five wickets at 17.80 at an economy rate of 5.56 as Australia were eliminated in the semi-finals by the hosts.

In the subsequent Rose Bowl series, she made her maiden international century, 113 not out in Invercargill, ending the eight ODIs with 343 runs at 57.16 and 12 wickets at 13.25.

[4] Nitschke made her debut for South Australia at the relatively old age of 24, playing in all of her state's eight matches in the 2000–01 Women's National Cricket League (WNCL).

At this stage of her career, Nitschke was effectively a specialist batter, and she took her only wicket of the season on the following day, taking 1/9 from three overs—the only time she bowled during the season—and scoring five as New South Wales won again.

[5] Nitschke did not pass 15 until the sixth match of the season, scoring 43 to help guide South Australia to a six-wicket win over Queensland.

[5] South Australia won five of their eight matches and did not make the final, but Nitschke scored 190 runs at 27.14 and took seven wickets at 16.57 with an economy rate of 2.57.

[5] The late-season form was enough for Nitschke to be retained for the Rose Bowl series against New Zealand held in Western Australia before the Australians departed to South Africa for the 2005 World Cup.

[5] In the northern hemisphere summer of 2005, Australia toured England and Nitschke established her batting at international level on this campaign.

She bowled top-scorer Charlotte Edwards for 69 to take her maiden Test wicket and then removed Jenny Gunn and Katherine Brunt at the end of the innings.

However, Australia's chances of saving the match was struck a blow at the start of the final day when Blackwell was out for 72 without further addition to the score and Julia Price was out for a first-ball duck.

South Australia won four of their eight matches and failed to reach the finals series, but Nitschke was productive, scoring 287 runs at 41.00 and taking nine wickets at 32.44 at an economy rate of 4.42.

[6] The following 2006–07 season started with the Rose Bowl series against New Zealand, which the Australians hosted at Allan Border Field in Brisbane.

In the first match, Nitschke made 33 as Australia amassed 9/260 but her bowling was attacked by New Zealand, who took 35 runs with the loss of only one wicket from her seven overs en route to a six-wicket win.

Australia won the next four matches to reach the final, but Nitschke continued to make starts without capitalising, registering scores of 21, 14, 21 and 13.

Again pushed up to open, she top-scored with 81 from as many balls, hitting 12 fours and a six to help set up a six-wicket win to take the competition.

[5] Australia hosted the Rose Bowl series held in tropical Darwin in July 2007, the middle of the southern hemisphere winter.

Nitschke made 14 and took 1/23 from four overs as Australia won the T20 international against England at the Melbourne Cricket Ground.

Returning for the final match at Manuka Oval in Canberra, she took 2/16 from her ten overs, and then top-scored with 94 as Australia made 3/178 to win by seven wickets and complete a 5–0 whitewash.

[5] In a warm-up matches against England ahead of the World Cup in New South Wales and Canberra, Nitschke made six and took 2/31 from eight overs.

The Australians hosted New Zealand for a three-match series in tropical Darwin at the beginning of June before the World Cup, and Nitschke played in the first two matches, making 1 and 25 and taking 1/27 and 1/14, both from four overs.

Arriving in the northern hemisphere she made 16 and was hit for 18 runs from two overs in the team's only warm-up on English soil, a five-run win against the hosts.

After hitting 119 not out and 66 in the double-header against the Australian Capital Territory, she made 12 and 82 against Western Australia, before striking her second century in five innings, 109 against Queensland.

Her best figures of 2/26 came in the final match against New South Wales and she ended with 10 wickets at 36.50 and an economy rate of 4.10, a poor bowling season by her standards.

Nitschke took 2/29 from ten overs in the next match and made 44 not out in an unbroken opening stand of 163 with Leah Poulton to guide Australia to a ten-wicket win.

Nitschke was attacked on the first day, conceding 18 runs from three overs without taking a wicket, before opening the batting and scoring 113 not out of the tourists' 4/256 in a six-wicket win, registering her maiden ODI century.