In 2000, she won her first WTA singles title in Shanghai, defeating Iroda Tulyaganova in the final, and breaking into the top 50.

11, won the second singles title of her career in Quebec City, and reached the finals of Hamburg and her home tournament in Scottsdale, Arizona.

She also reached the quarterfinals or better of four other tournaments that year,[2] with wins over top five players Jelena Dokić and Serena Williams.

However, she obtained the best doubles results of her career, winning seven tournaments with partner Nadia Petrova, including the WTA Tour Championships in Los Angeles.

Her year began with a right leg injury, which forced her to withdraw from the Australian Open doubles competition, and from a tournament in Hyderabad, India.

However, she showed signs of recovery in February, reaching the final of Memphis, defeating Nicole Vaidišová in the semifinals.

After Memphis, Shaughnessy struggled with back injuries for the duration of the spring, not reaching another semifinal until June at the Ordina Open in 's-Hertogenbosch, Netherlands.

9 seed Nathalie Dechy for the first time in ten attempts,[8] before losing to doubles partner Anna-Lena Grönefeld in the second round.

The pair reached the doubles finals of the 2011 Indian Wells Open, by successively defeating Alisa Kleybanova & Yan Zi, Raquel Kops-Jones & Abigail Spears, Liezel Huber & Nadia Petrova and Victoria Azarenka & Maria Kirilenko, but lost to Sania Mirza and Elena Vesnina in the finals.

Shaughnessy was in a relationship with her coach Rafael Font de Mora; they met when she was 13 and she moved in with him a year later.

[12] Shaughnessy was in a relationship with Major League Baseball player Roberto Alomar from 2004 to 2006, whom she alleged had exposed her to HIV.