During the 2001–02 season, Blackwell made her senior debut for New South Wales.
In her first match against Queensland, she bowled two expensive overs, conceding 18 runs, and was not required to bat as New South Wales won by six wickets.
Batting in the middle-order, often lower than the top-six, Blackwell as only required to bat once in her first four matches, making nine not out in the second match against Queensland and being at the crease when the six-wicket win was registered.
The season was interrupted by the national Under-19 competition, and Blackwell was prominent with both bat and ball as New South Wales won all of their six matches.
Apart from one duck, Blackwell reached 30 in her remaining five innings to aggregate 207 runs at 41.40.
She also took 11 wickets at 9.36.
In five of the six matches, she scored at least 30 and took two or more wickets.
Blackwell returned to senior duty and again had little to do in the lower order as her state's leading batsmen encountered little difficulty with opposition bowlers.
New South Wales defeated Victoria in both round-robin matches and beat them again in the finals series 2–0 to win their sixth consecutive national title.
Blackwell was at the crease, unbeaten on 12, as New South Wales reached their target in the second match with four wickets in hand, having not been required to bat in the seven-wicket win in the first final the day before.
Blackwell played in eight matches but was only required to bat four times for a total of 33 runs at 33.00 and bowled seven overs without success.

At the end of the season, Blackwell was selected for the Australia Youth team that played New Zealand A. She made 76 runs at 19.00 in four matches with a highest score of 32 and took a total of 1/43 from 11 overs.
This was followed by a match against the senior New Zealand team.
Blackwell took 1/18 and scored 2 in a 21-run defeat.

In 2002–03, Blackwell played in her first full season in the WNCL, taking to the field in all 10 of New South Wales' matches.
After not being trusted to bat at No.
7 or higher in the first match of the season, which New South Wales won, Blackwell was unbeaten on 17 when they lost to South Australia in the second match of the double-header the next day, having been attacked and conceded 23 runs from two overs in South Australia's innings.
Blackwell made her maiden half-century at senior level in the next match, scoring 74 not out to guide her state of a five-wicket win over Victoria.
She then made three single-digit scores before rediscovering form in the last two round-robin matches against Western Australia, making 36 and 38.
New South Wales won six matches of their eight matches and faced Victoria in the final.
Blackwell made only 14 and 17 as New South Wales lost both of the finals, ending their run of six WNCL titles in a row.
In the second final, she took her maiden wicket at senior level, but her sporadic bowling was otherwise unsuccessful, conceding 45 runs in 8 overs for the season.
Blackwell ended the season with 212 runs at 30.28.
During the 2001–02 season, Blackwell made her senior debut for New South Wales. In her first match against Queensland, she bowled two expensive overs, conceding 18 runs, and was not required to bat as New South Wales won by six wickets. Batting in the middle-order, often lower than the top-six, Blackwell as only required to bat once in her first four matches, making nine not out in the second match against Queensland and being at the crease when the six-wicket win was registered. The season was interrupted by the national Under-19 competition, and Blackwell was prominent with both bat and ball as New South Wales won all of their six matches. Apart from one duck, Blackwell reached 30 in her remaining five innings to aggregate 207 runs at 41.40. She also took 11 wickets at 9.36. In five of the six matches, she scored at least 30 and took two or more wickets. Blackwell returned to senior duty and again had little to do in the lower order as her state's leading batsmen encountered little difficulty with opposition bowlers. New South Wales defeated Victoria in both round-robin matches and beat them again in the finals series 2–0 to win their sixth consecutive national title. Blackwell was at the crease, unbeaten on 12, as New South Wales reached their target in the second match with four wickets in hand, having not been required to bat in the seven-wicket win in the first final the day before. Blackwell played in eight matches but was only required to bat four times for a total of 33 runs at 33.00 and bowled seven overs without success.
At the end of the season, Blackwell was selected for the Australia Youth team that played New Zealand A. She made 76 runs at 19.00 in four matches with a highest score of 32 and took a total of 1/43 from 11 overs. This was followed by a match against the senior New Zealand team. Blackwell took 1/18 and scored 2 in a 21-run defeat.
In 2002–03, Blackwell played in her first full season in the WNCL, taking to the field in all 10 of New South Wales' matches. After not being trusted to bat at No. 7 or higher in the first match of the season, which New South Wales won, Blackwell was unbeaten on 17 when they lost to South Australia in the second match of the double-header the next day, having been attacked and conceded 23 runs from two overs in South Australia's innings. Blackwell made her maiden half-century at senior level in the next match, scoring 74 not out to guide her state of a five-wicket win over Victoria. She then made three single-digit scores before rediscovering form in the last two round-robin matches against Western Australia, making 36 and 38. New South Wales won six matches of their eight matches and faced Victoria in the final. Blackwell made only 14 and 17 as New South Wales lost both of the finals, ending their run of six WNCL titles in a row. In the second final, she took her maiden wicket at senior level, but her sporadic bowling was otherwise unsuccessful, conceding 45 runs in 8 overs for the season. Blackwell ended the season with 212 runs at 30.28.
Alex Blackwell