Question: Marc Polmans, with Andrew Whittington, reached the semi-final of a tennis tournament where who were the defending champions?

Context paragraphs:
2006 French Open: The 2006 French Open was a tennis tournament that took place on the outdoor clay courts at the Stade Roland Garros in Paris, France from May 28 to June 11, 2006.  It was the 105th staging of the French Open, and the second of the four Grand Slam tennis events of 2006.  This edition made history as it became the first Grand Slam tournament to start on a Sunday.  It was the 2nd time since 1985 that all top 4 seeds reached the semi-finals in the men's singles of a Grand Slam tournament.  This did not happen again until the same tournament 5 years later.  Both defending champions, Rafael Nadal and Justine Henin-Hardenne, retained their titles.

1999 WTA German Open – Doubles: The 1999 WTA German Open – Singles was the singles event of the fifty-fifth edition of the tennis tournament played at Berlin, Germany, the most prestigious tennis tournament in Latin Europe.  It was the sixth WTA Tier I tournament of the year, and part of the European claycourt season.  Lindsay Davenport and Natasha Zvereva were the defending champions, but only Zvereva participated this year with Mary Pierce.  They were eliminated in the first round by Brie Rippner and Tara Snyder.

2013 Bendigo Women's International (2): The 2013 Bendigo Women's International (2) was a professional tennis tournament played on outdoor hard courts.  It was the sixth edition of the tournament (second of the year) which was part of the 2013 ITF Women's Circuit, offering a total of $50,000 in prize money.  It took place in Bendigo, Australia, on 28 October–3 November 2013.  Rodionova, Barty and Peers were listed as the defending champions as they were the champions of the event last year, as there were two events in 2013 they are listed as defending champions for both editions.

2017 Australian Open – Men's Doubles: Jamie Murray and Bruno Soares were the defending champions, but lost in the first round to Sam Querrey and Donald Young.

2016 Australian Open – Boys' Doubles: Jake Delaney and Marc Polmans were the defending champions, however both players were no longer eligible to play juniors.

Jake Delaney: Jake Delaney (born 14 May 1997 in Sydney) is an Australian tennis player.  Delaney won the 2015 Australian Open – Boys' Doubles title with fellow Australian Marc Polmans, defeating Hubert Hurkacz and Alex Molčan in the final, 0–6, 6–2, [10–8].

2016 Tallahassee Tennis Challenger – Doubles: Dennis Novikov and Julio Peralta were the defending champions and successfully defended their title, defeating Peter Luczak and Marc Polmans 3–6, 6–4, [12–10] in the final.

1999 Italian Open – Women's Doubles: The 1999 Italian Open – Doubles was the doubles event of the fifty-fifth edition of the tennis tournament played at Rome, Italy, the most prestigious tennis tournament in Southern Europe.  It was the fifth WTA Tier I tournament of the year, and part of the European claycourt season.  Virginia Ruano Pascual and Paola Suárez were the defending champions, but lost to Martina Hingis and Anna Kournikova in the quarterfinals.

Marc Polmans: Marc Polmans (born 2 May 1997) is a South African born Australian tennis player.  Polmans won the 2015 Australian Open – Boys' Doubles title with fellow Australian Jake Delaney, defeating Hubert Hurkacz and Alex Molčan in the final, 0–6, 6–2, [10–8].  He reached the semi-final of the 2017 Australian Open – Men's Doubles with Andrew Whittington.

2015 Australian Open – Men's Doubles: Łukasz Kubot and Robert Lindstedt were the defending champions, but chose not to participate together.  Kubot teamed up with Jérémy Chardy, but lost in the second round to Alex Bolt and Andrew Whittington.  Lindstedt played alongside Marcin Matkowski, but lost in the second round to Jonathan Erlich and Treat Huey.

Supporting paragraphs: Marc Polmans 2017 Australian Open – Men's Doubles
Answer: Jamie Murray and Bruno Soares