Daniil Medvedev has withdrawn from the Kremlin Cup due to fatigue, and therefore will not bid to reach his seventh consecutive final this week.
Russian news agency Tass quoted Medvedev as saying that he felt "drained psychologically and physically" after his Shanghai victory.
The 23-year-old leads the ATP in victories with 59 wins in 76 total matches this season. He has won titles at Sofia, Cincinnati, St. Petersburg and Shanghai, in addition to reaching his first Grand Slam final at this year’s US Open.
Medvedev was replaced in the draw by lucky loser Nikola Milojevic.
Defending champion and second seed Karen Khachanov is the highest remaining seed in the tournament.