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Russians Karen Khachanov (20) and Daniil Medvedev (17) led the ATP Tour in match wins indoors in 2018.

Rising Russians: Indoor Excellence Keys Khachanov & Medvedev's Surge

2017 Next Gen ATP Finals qualifiers led ATP Tour in 2018 in indoor match wins

This time last year, there were no Russians placed inside the Top 30 of the ATP Rankings. But entering the first indoor stretch of the 2019 ATP Tour season, there are two Russians inside the Top 20.

World No. 11 Karen Khachanov and World No. 16 Daniil Medvedev's surges can be in part explained by their performance indoors in 2018. According to the FedEx ATP Performance Zone, Khachanov and Medvedev made their biggest breakthroughs with roofs over their heads, winning more matches indoors than anyone else last year.

Most Indoor Match Wins In 2018

 Player  Indoor Record
 1. Karen Khachanov  20-4 
 2. Daniil Medvedev  17-7
 3. Kei Nishikori  16-7
 4. Roger Federer  14-3
 T5. Kevin Anderson  13-4
 T5. Stefanos Tsitsipas  13-6

When Khachanov began his first tournament after the 2018 Australian Open, the Open Sud de France in Montpellier, he was the No. 49 player in the ATP Rankings, and held just a 7-16 record indoors. But the powerful right-hander led the circuit in both wins (20) and titles (3) indoors last season.

Khachanov tallied a 20-4 mark (83.3%). Only five players all-time have an indoor win-rate of more than 80 per cent. No effort stood out more than his performance at the Rolex Paris Masters.

Entering the final ATP Masters 1000 event of the year, Khachanov owned a 14-17 record at the elite level. But he defeated four Top 10 players — including current World No. 1 Novak Djokovic in the final — en route to the biggest trophy of his career. It was his third indoor title in 2018 after also triumphing in Marseille and Moscow.

Medvedev, who was World No. 56 this time last year, also made his mark indoors in 2018, earning a 17-7 record to make him 28-16 indoors for his career. The Russian claimed his biggest title in Tokyo at the Rakuten Japan Open Tennis Championships, defeating home favourite Kei Nishikori in the final. He won 32 of his final 33 service points. The only set Medvedev lost at the ATP 500 event came in the second round of qualifying.

Medvedev also advanced to the semi-finals at two more indoor tournaments: Moscow, where he lost to Khachanov, and Basel, where he lost to Roger Federer. The Russian is off to a fast start indoors in 2019, winning the Sofia Open for his fourth title.

Federer ranked second on the ATP Tour in winning percentage indoors last year, emerging victorious in 82.4 per cent of his clashes. The 99-time tour-level champion earned indoor titles in Rotterdam and Basel.

Rounding out the Top 5 in winning percentage indoors are Djokovic (80.0%), Kevin Anderson (76.5%) and Dominic Thiem (75.0%). Anderson, who had not lifted a trophy since 2015, triumphed in New York and Vienna. Thiem won his first career indoor title in St. Petersburg.

Best Winning Percentage Indoors In 2018

 Player  Record  Winning Percentage
 1. Karen Khachanov  20-4  83.3%
 2. Roger Federer  14-3  82.4%
 3. Novak Djokovic  8-2  80.0%
 4. Kevin Anderson  13-4  76.5%
 5. Dominic Thiem  12-4  75.0%