She was introduced to tennis by her mother, Françoise Paszek, at age four-and-a-half. Her mother is Chilean born, and her father is Ariff Mohamed, who is Tanzanian-born, Kenya-raised and lived in Canada.Both her paternal grandparents are from India.[citation needed] She is currently being coached by Angel Giminez having previously been coached by Larri Passos (former coach of former ATP No.1 Gustavo Kuerten).
As a junior, Paszek was a finalist in the 2005 Girls' Singles Championship at Wimbledon and at the US Open – Girls' Singles in 2006.In September 2005 she won her first title at an ITF tournament in Sofia. In October of the same year she received a wild card to appear at her first WTA tournament in Linz; she defeated Elena Vesnina in the first round and lost to Ana Ivanović after a tough first set.
In 2006 she passed qualifications in Istanbul, where she lost in the second round to Catalina Castaño; and in Portorož in the Banka Koper Slovenia Open, where she won her first WTA title by defeating number 6 seed Maria Elena Camerin from Italy 7–5 6–1. This was a career-first Tour singles title in only her third Tour main draw. That title made her the youngest Tour singles titlist in 2006 and the seventh-youngest all-time, the youngest winner being Tracy Austin. A month later, at the Zürich Open, she lost to Camerin in the second round of qualifying. She finished 2006 as No. 181 in the WTA rankings.
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After her loss to Na Li in the second round of the Miami Masters, she broke the top 100 of the WTA rankings. At the 2007 French Open she was defeated by Justine Henin in the second round 7–5 6–1 after being 5–0 down in the first set.
At Paszek's first grass tournament of her career, she reached the third round in Birmingham, losing to Maria Sharapova in a tight match 6–3 4–6 6–2. At the 2007 Wimbledon Championships she reached the fourth round after beating two seeded players, No.17 seed Tatiana Golovin and No.12 seed Elena Dementieva; she then eventually lost to No.5 seed Svetlana Kuznetsova in straight sets. The win pushed her up 19 spots from #54 to #35, a career high and only a few spots from a guaranteed seeding spot at the US Open.
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She debuted on the 2007 US Open, reaching the fourth round, beating on the way #24 and #11 seed, Francesca Schiavone and Patty Schnyder. She lost to #6 seed, Anna Chakvetadze.
Paszek decided against defending her title in the Banka Koper Slovenia Open in Portorož, Slovenia, in favour of the larger China Open tournament in Beijing. However, she was bundled out in the second round by fourth-seeded Elena Dementieva (whom she beat in Wimbledon) 6–2, 6–0 in less than an hour.
At the 2008 ASB Classic in Auckland, New Zealand, Paszek made it to the semifinals, losing to veteran Lindsay Davenport 6–4, 6–3. In the first round of the 2008 Australian Open, Paszek played third-seeded Jelena Janković of Serbia in the first round. Paszek easily won the first set 6–2, and Janković went on to win the second set 6–2. In the deciding set, Paszek led 5–3 and had three match points before Janković came back to win the three-hour match 2–6 6–2 12–10.
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This started a losing streak of 6 straight matches running through the French Open and Wimbledon. At Wimbledon she lost her second marathon match of the year to Francesca Schiavone 6–3 5–7 10–8. It came to an end in Los Angeles where she defeated Aiko Nakamura only to lose to Flavia Pennetta in the second round.
On July 31, Paszek beat World no.1 Ana Ivanović of Serbia in the third round of the Rogers Cup in Montreal in three sets: 6–2, 1–6, 6–2. In the quarterfinals, she played Victoria Azarenka who defeated her 6–4 7–5. Then she lost in the first round of Cincinnati to Petra Cetkovská. At the US Open she defeated the 23-seed Maria Kirilenko 6–3 3–6 6–4, only then to lose to a lower ranked opponent Magdaléna Rybáriková.Paszek was runner up in Bali. She reached the final after taking out the 7-seed Flavia Pennetta and the top seed Daniela Hantuchová. She lost the final against Patty Schnyder 3–6 0–6. She then withdrew from the Linz tournament due to injury.
Paszek ended her professional relationship with coach Lari Passos and is now coached by Angel Giminez
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Her next tournament was 2010 Australian Open where she lost to Julia Görges in first round 6–0 3–6 6–3. At tournament in Paris Tamira lost to eventual runner-up Lucie Šafářová 6–0 6–3.To reach the main draw at 2010 Dubai Tennis Championships, Tamira entered qualifying. She defeated Tsvetana Pironkova in first round, but she lost to Anna-Lena Grönefeld 6–3 7–5. After Dubai she entered in Indian Wells, but she lost to Julie Coin with 6–4 6–3 score. At 2010 Sony Ericsson Open, Tamira beat Anne Keothavong 6–4 6–2, but she lost to 22-th seed Anastasia Pavlyuchenkova 7–6 4–6 6–3
She lost in early rounds of Marbella, Barcelona and Fes. She didn't enter to 2010 French Open
Instead,Tamira entered 25,000 $ ITF tournament in Izmir, Turkey. She won that tournament beating Çağla Büyükakçay 6–2 6–3. Her next tournament was ITF Budapest. She successfully qualified defetaing Lukacs Vanda and Cepelova Jana, and she reached second round losing to Lenka Wienerová.
She then entered 2010 Wimbledon, qualified but lost to Kurumi Nara in second round 7–5 6–4.
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Her next tournament was the 2010 Banka Koper Slovenia Open where she defeated Jelena Kostanić Tošić 7–5 6–2 for her first main draw win since Ponte Vedra Beach in 2009.
After some bad losses in qualifying of the Premier tournaments, Tamira found her form in the 2010 US Open where she entered qualifying. She defeated Michaëlla Krajicek, Koreas Kim So- Jing and Russias Evgeniya Rodina to reach the main draw. In the final qualifying round, Paszek trailed Rodina 2–6 after the first set before coming back to win the second and blank the Russian in the third. In the 1st round of the main draw, she defeated 26th seed Lucie Šafářová despite being down 2–6 1–4 in the second set. She lost to Chan Yung-jan in the second round.
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She will be in the 100 rankings again.
2011: Tamira started 2011 ranked No.89 and lost in the first round of Auckland to Sofia Arvidsson. She qualified for Hobart and reached the second round of the main draw before falling to Jarmila Gajdosova. Prior to Wimbledon 2011 Tamira had a standard year before she went on to reach the Quarter Finals of Wimbledon for the first time in her career, defeating world No.7 and 6th seed Francesca Schiavone (her first top 10 win of 2011) in an epic third round match that lasted 3 hours and 42 minutes. Tamira finally prevailed 3–6, 6–4, 11–9 hitting a total of 40 winners to 36 unforced errors. Tamira played Russian Ksenia Pervak in the fourth round. She went on winning, beating Pervak in three sets: 6–2, 2–6, 6–3, reaching the quarterfinals of a Grand Slam for the first time. Tamira played number 4 seed Victoria Azarenka in the Quarter Finals of Wimbledon. The match started on Court 1 but was moved to Centre Court after the first game due to rain. Paszek lost in straight sets 6–3, 6–1.