Matt Lucena (born August 4, 1969) is a former professional tennis player from the United States.
 He won the mixed doubles title at the 1995 US Open.
The 2013 International German Open (also known as the bet–at–home Open – German Tennis Championships 2013 for sponsorship reasons) was a men's tennis tournament played on outdoor red clay courts.
 It was the 107th edition of the event known that year as the International German Open and was part of the ATP World Tour 500 series of the 2013 ATP World Tour.
 It took place at the Am Rothenbaum in Hamburg, Germany, from 14 July through 22 July 2013.
 Twelfth-seeded Fabio Fognini won the singles title.
Fabio Fognini was the defending champion but decided not to participate.
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Fabio Fognini and Robert Lindstedt were the defending champions, but chose not to participate this year.
Fabio Fognini (] ; born 24 May 1987) is an Italian professional tennis player who is currently ranked world No. 29 in men's singles by the Association of Tennis Professionals (ATP) and the current Italian No. 1.
 His career-high singles ranking is world No. 13, achieved in March 2014, and world No. 7 in doubles, achieved in July 2015.
 Fognini's most successful surface is red clay, upon which he won his four ATP singles titles in Stuttgart, Hamburg, Viña del Mar and Umag, reached the quarterfinals of the 2011 French Open and the semifinals of the 2013 Monte-Carlo Masters.
 Together with Simone Bolelli, Fognini won the 2015 Australian Open doubles event, becoming the first all Italian men's pair to win a Grand Slam title in the Open era.
Fabio Fognini was the defender of title; however, he chose to not participate this year.
Fabio Fognini was the defending champion, but chose not to play.
Fabio Fognini chose to not defend his 2009 title.
Thomaz Bellucci was the defending champion, but lost to Fabio Fognini in the quarterfinals.
Fabio Fognini was the defending champion, but lost in the semifinals to Roberto Bautista Agut.
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Question: Matt Lucena and Fabio Fognini, have which mutual occupation?
Answer: professional tennis player