World No 1 and tournament organiser Djokovic followed up his wins over Borna Coric and Pefja Krstin on Saturday with a 4-1 4-3(3) victory over Nino Serdarusic.
Rublev also remained unbeaten after an impressive 4-2 4-1 win over Alexander Zverev saw him reach the final, which takes place at 7pm BST, live on Eurosport 2.

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Rublev saved three break points at 2-2 in the first set and then broke serve in the next game to move ahead.
World No 7 Zverev did break in the first game of the second set but lost the next four games in a row to suffer his second defeat of the weekend.
Djokovic was relatively comfortable in his victory over Serdarusic, who entered the tournament on Saturday after Grigor Dimitrov’s withdrawal.

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Serdarusic had chances in the opening set but spurned six break points. He was then outclassed in the second-set tiebreak as Djokovic secured the win.
Meanwhile, Coric bounced back from defeat to Djokovic on Saturday with a 4-3 (4), 4-3 (2) win over Krstin and Danilo Petrovic beat Marin Cilic 4-2 4-2.
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