Question: Were Alex O'Brien and Maria Sharapova both professional tennis players?

Context articles: Alex Kuznetsov
Robert Lansdorp
Rick Macci
2014 Maria Sharapova tennis season
Maria Sharapova
Bosworth Tennis
Alex O'Brien
Rossana de los Ríos
Tatiana Golovin
Marta Domachowska

Oleksandr "Alex" Kuznetsov (born February 5, 1987) is a retired American professional tennis player.
 He currently works as the main hitting partner of Maria Sharapova.
Robert Lansdorp (born 1938, Semarang, Indonesia) is a professional tennis coach.
 He first rose to international fame in 1979 when his student Tracy Austin became the youngest US Open Women's Singles champion in history at age 16.
 He has gone on to coach other tennis champions including Pete Sampras, Lindsay Davenport, and Maria Sharapova.
 He is regarded as an expert on groundstrokes, in particular the forehand, advocating a powerful, flat hitting technique commonly referred to as the "Lansdorp Forehand".
Rick Macci (born December 7, 1954) is a United States Professional Tennis Association (USPTA) Master Professional, and seven-time USPTA national coach of the year who has trained five number one ranked players—Andy Roddick, Jennifer Capriati, Maria Sharapova, Serena Williams, and Venus Williams.
The 2014 Maria Sharapova tennis season officially began on 30 December 2013 with the start of the 2014 WTA Tour.
 Sharapova began the season, having only played one match since the previous June due to a shoulder injury, at the Brisbane International.
 After failing to defend her points during the winter and spring hard court season, Sharapova almost dropped out of the Top 10.
 She rebounded by dominating the clay court season which saw her win Stuttgart, Madrid and the French Open.
 Her only loss on clay came to a resurgent Ana Ivanovic.
 She then won her first hard court title since the 2013 BNP Paribas Open at the China Open.
 Her season ended on 24 October 2014 following her elimination from the round robin stage at the 2014 WTA Finals in Singapore.
 She ended the year raned No. 2 behind Serena Williams.
Maria Yuryevna Sharapova (Russian: Мари́я Ю́рьевна Шара́пова ; ] ; born April 19, 1987) is a Russian professional tennis player.
 A United States resident since 1994, Sharapova has competed on the WTA tour since 2001.
 She has been ranked world No. 1 in singles by the WTA on five separate occasions, for a total of 21 weeks.
 She is one of ten women, and the only Russian, to hold the career Grand Slam.
 She is also an Olympic medalist, having earned silver for Russia in women's singles at the 2012 Summer Olympics in London.
Bosworth Tennis, also known as Bosworth International, is a family business which specializes in stringing tennis rackets but also designs and alters other aspects of tennis rackets to match the personal preferences of the players.
 They have worked with many of the top tennis players, notably Ivan Lendl.
 The company was created by Warren Bosworth in 1975.
 By 1992 his business moved from Glastonbury, Connecticut to Boca Raton.
 It is now led by his son Jay Bosworth, who joined the company in 1982.
 It is one of a handful of highly specialized companies catering to the top professional players, compabarable to Roman Prokes (Maria Sharapova, Andy Roddick) and Nate Ferguson (Roger Federer, Novak Djokovic), but they also provide similar services to amateur players.
Alex O'Brien (born March 7, 1970 in Amarillo, Texas) is a retired professional tennis player from the United States, who competed on the ATP Tour.
 He became the world No. 1 doubles player in May 2000 and was ranked as high as world No. 30 in singles in June 1997.
Rossana de los Ríos (born 16 September 1975) is a retired professional tennis player from Paraguay.
 She was born in the Paraguayan capital, Asunción, and now lives in Miami, USA, with her daughter Ana Paula Neffa de los Ríos and her husband Gustavo Neffa, a retired Paraguayan Association football player who played for Boca Juniors.
 Rossana achieved a career high singles ranking of No. 51 on 12 September 2001, and No. 52 in doubles on the Sony Ericsson WTA Tour.
 De los Ríos played doubles with Grand Slam champions such as Maria Sharapova, Svetlana Kuznetsova, Arantxa Sánchez Vicario, as well as Jelena Janković and Dinara Safina.
 Rossana is also a former world number one Junior player, having won the 1992 Roland Garros Juniors event.
 De los Ríos participated in six editions (1994, 2001, 2002, 2003, 2009 and 2010) of the Australian Open.
 She was the only female tennis representative for Paraguay in the 1992 and 2000 Olympic Games.
Tatiana Golovin (Russian: Татья́на Григорьевна Голови́на , "Tatyana Grigoryevna Golovina" ; born 25 January 1988) is a Russian-born French retired professional tennis player.
 She won the 2004 French Open mixed doubles event with Richard Gasquet, and reached the singles quarterfinal at the 2006 US Open, losing to the eventual champion Maria Sharapova.
 Her highest singles ranking to date is 12.
 In 2008, she was diagnosed with lower back inflammation and was forced to stop playing competitive tennis indefinitely.
Marta Domachowska (; born 16 January 1986 in Warsaw) is a Polish retired professional tennis player ranked World No. 37 in singles (2006) and World No. 62 in doubles (2006).
 She reached 2008 Australian Open fourth round in singles and won 2006 Canberra International in doubles with Roberta Vinci.
 She also reached three WTA Tour singles finals at 2004 Hansol Korea Open (lost to Maria Sharapova), 2005 Internationaux de Strasbourg (lost to Anabel Medina Garrigues) and 2006 U.S. National Indoor Tennis Championships (lost to Sofia Arvidsson).
 She was 2003 Australian Open finalist in girls' singles, represented Poland at the 2008 Summer Olympics and was member of Poland Fed Cup team.
 Domachowska was the best female Polish tennis player after Magdalena Grzybowska's retirement and before Agnieszka Radwańska's successes.