Daniil Medvedev lost his opening match at the ATP Finals to fellow Russian Andrey Rublev, 7-6, 3-6, 6-7.It was a disappointing start for Medvedev who has produced some of his best tennis at the ATP Finals in the last couple of years, reaching the final last year and winning the title in 2020.Medvedev was unable to overcome Rublev in their two hour, 31 minute long battle on Monday despite producing some quality tennis and taking the first set.Consistency was an issue for the Russian, who admitted in his post-match press conference that he was not feeling his best during the clash.‘’There are some matches where you feel you’re untouchable, and every …