#2. Dominic Thiem
The 23-year old Austrian produced a couple of exciting performances in 2014 and 2015, ending 2015 in the Top 20 of the ATP rankings. This year, Thiem began by reaching the semi-finals of the Brisbane International which was followed by a disastrous second round exit at the Sydney International. At the Australian Open, Thiem was knocked out in the third round by David Goffin.Following the Australian Open, Thiem won his fourth ATP title at the Argentina Open where he upset Rafael Nadal in the semi-finals before defeating Nicolas Almagro in the final. His good form persisted as he reached the semi-finals of the Rio Open, upsetting David Ferrer en route which was followed by his second ATP title at the Mexican Open. He ended his hard-court season with round-of-16 finishes at the Indian Wells and Miami Masters.He began his clay-court season with a third round finish at the Monte-Carlo Masters which was followed by a runner-up performance at the BMW Open. After losing to a resurgent Juan Martin Del Potro at the Madrid Masters, Thiem reached the quarter-finals of the Rome Masters.
Thiem won his third ATP title of the year by successfully defending his title at the Open de Nice, and ended his clay-court season on a brilliant note by reaching his first Grand Slam semi-final at Roland Garros where he beat David Goffin in the quarter-finals, thus avenging his Australian Open defeat to the Belgian. He lost to eventual champion Novak Djokovic in the semis in straight sets. Following the tournament, Thiem reached a career-high ranking of World No.7.Thiem began his grass-court season on a winning note by winning his fourth ATP title of the year at the Mercedes Cup where he beat Roger Federer in the semis before defeating Philipp Kohlschreiber in the final. It was also the first grass-court tournament win of his career. After exiting the Gerry Weber Open in the semi-finals, Thiem was stunned in the second round of Wimbledon by Czech Jiri Vesely.The Wimbledon was followed by disappointing performances at the Austrian Open and the Rogers Cup. Thiem bounced back by reaching the quarter-finals of the Cincinnati Masters. At the US Open, Thiem reached the fourth round where he had to retire against Juan Martin Del Potro due to a knee injury.Following the US Open, Thiem reached the final of the Moselle Open where he lost to an in-form Lucas Pouille in straight sets. Thiem had a patchy Asian swing with quarter-final and first round exits at the Chengdu Open and China Open respectively. This was followed by second round exits at the Vienna Open and the Paris Masters. The withdrawal of Rafael Nadal from the remainder of the ATP World Tour meant that Thiem would qualify for the World Tour Finals for the first time in his career.At the World Tour Finals, Thiem lost his opening round robin match to Djokovic in three sets but won his second match against Gael Monfils to keep his semi-final hopes alive. In his final round robin match, he was beaten by Milos Raonic and was eliminated from the tournament.The year-end World No.8 did not have the best of endings to the year but he has produced quite a number of good performances this year and provided he is consistent, he could be a top contender for a Grand Slam next year around.