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Dominic Thiem has won more than 88 per cent of his deciding sets in 2019.

Deciding-Set Dominic: Where Thiem Has Dominated In 2019

ATPTour.com uses the FedEx ATP Performance Zone to examine deciding-set performance

Editor's Note: This story was originally published on 22 October. Dominic Thiem has gone 5-0 in deciding sets since then, improving to 15-2 in 2019.

The world’s best are battling at the Nitto ATP Finals. And on Tuesday evening, Dominic Thiem defeated Novak Djokovic in a third-set tie-break to move to 2-0 in Group Bjorn Borg play.

And although Thiem's victory was an upset against the five-time season finale champion, it was no surprise that the Austrian won a deciding set.

The 26-year-old had only emerged victorious in 60 per cent of his tour-level deciding sets prior to the season. But Thiem has won 15 of his 17 deciding sets in 2019, a success rate of more than 88 per cent. That leads the ATP Tour in 2019 for players who have contested at least 10 deciding sets.

2019 Leaders - Deciding Sets Won

 Player  Record  Winning Percentage
 1. Dominic Thiem  15-2  88.2%
 2. Andrey Rublev  12-4  75.0%
 3. Cristian Garin  11-4  73.3%
 4. Laslo Djere  8-3  72.7%
 5. Alexander Bublik  10-4  71.4%
*(at least 10 deciding sets played)
What is most glaring is when those deciding sets have come. Thiem has gone to a deciding set in five tour-level semi-finals, emerging victorious four times. He also went to a deciding set in three championship matches, clinching the title on each occasion. In those title clashes alone — at the BNP Paribas Open, the China Open and the Erste Bank Open — he could have earned 800 fewer ATP Ranking points with losses.

The players directly behind him have also enjoyed the best seasons of their careers. Andrey Rublev (75.0%), Cristian Garin (73.3%), Laslo Djere (72.7%) and Alexander Bublik (71.4%) have all reached their career-high ATP Ranking in 2019, and they occupy the second through fifth spots in rate of deciding sets won this season.

The five active players with the best all-time winning percentages in deciding sets are not inside the Top 10 this year. Kei Nishikori (60%), Novak Djokovic (46.7%), Rafael Nadal (66.7%), Andy Murray and Juan Martin del Potro lead their peers in this FedEx ATP Performance Zone. Nadal has only played six deciding sets this year, going 4-2 in those matches. Both Murray and Del Potro have played less than 10 deciding sets, mostly because they have missed time due to injury.

Career Leaders - Deciding Sets Won (Active Players)

 Player  Record  Winning Percentage
 1. Kei Nishikori  132-46  74.2%
 2. Novak Djokovic  176-65  73.0%
 3. Andy Murray  159-73157-71  68.9%
 4. Rafael Nadal  159-73  68.5%
 5. Juan Martin del Potro  97-47  67.4%

The only player competing at The O2 in London who has not won at least half of his deciding sets this year is Novak Djokovic, who has triumphed in 46.7 per cent of those matches (7-8). The Serbian has still managed to put himself in position to battle for year-end No. 1 with Rafael Nadal

Did You Know?
Thiem is the first singles player to advance to the semi-finals of this year's Nitto ATP Finals.