Denis Istomin has pulled off one of the great grand-slam shocks by knocking out six-time Australian Open champion Novak Djokovic in the second round in Melbourne.
The 30-year-old Uzbek won 7-6 (10/8) 5-7 2-6 7-6 (7/5) 6-4 and will face Pablo Carreno Busta in round three.
Here, Press Association Sport lists five things you need to know about Istomin.
1. He is unique among current leading male players in being coached by his mum, Klaudiya Istomina - a keen amateur player who introduced her son to the game. Istomin said: " We have a good relationship and we understand each other very well. She always tries to help me with everything, not just tennis, normal life as well. She gives me good words to improve my tennis, my life, everything. I'm happy to be coached by my mum."
2. Istomin's ranking of 117 was not high enough to earn him direct entry into the tournament. His route in was via a wild card awarded to the winner of an Asia-Pacific play-off event. Istomin was the top seed but had to save four match points in the semi-finals against India's world number 319 Prajnesh Gunneswaran before defeating Lee Duck-hee of South Korea in the final.
3. Istomin's career was nearly over before it began. Aged 14, he was involved in a car crash on his way to a tournament. He suffered serious leg injuries, requiring 80 stitches, and spent three months in hospital. Istomin did not pick up a racket for two years and was ready to give up the sport before his mum persuaded him to give it another try.
4. He has twice made the fourth round at grand slams - at Wimbledon in 2012 and at the US Open in 2013. His highest ranking was 33 in 2012 while this was just his second win in 34 attempts against top-10 players - the first came against David Ferrer in Indian Wells five years ago. Istomin's only ATP Tour title came on grass at the Nottingham Open in 2015.
5. Istomin is the only player representing Uzbekistan in the world's top 300. He was born in the Russian town of Orenburg but his Uzbek father OIeg moved the family to Tashkent when Istomin was a baby. He has a brother, Anton, who is 14 years younger. The only time he was not coached by his mother was when Anton was very young.
Source: PA
