Novak and Daniil met for the 11th time in a highly anticipated semi-final match at the Astana Open on Saturday. The two players were level at one set apiece, 4-6, 7-6 (6), when the second seed decided to pull out due to a leg injury.
Novak and Fabio Fognini missed on a great opportunity to beat doubles specialists Lukasz Kubot (POL) and Marcelo Melo (BRA) and reach finals at the BNP Paribas Open. The Serbian/Italian duo lost a tight contest 6-7 (5), 6-2, 6-10 after one hour and 40 minutes of play
Nole will take on Gael Monfils (2) on Saturday, seeking his first title on grass outside Wimbledon.
Novak maintained his winning start to 2017 season with a hard-fought 4-6, 7-6 (7), 6-3 victory over Fernando Verdasco on Friday.
Sunday's contest between Novak and Andy Murray will be the first occasion in history that the year-end no.1 ranking is on the line at the title-match of the season finale.
Novak beat no.10 seed Gael Monfils 6-3, 6-2 on Saturday in the semi-finals and improved to a 50-4 match record on the season.
With a 6-3, 6-1, 6-4 victory over 13th seed Dominic Thiem, Nole is one match win away from completing a career Grand Slam.