BELGRADE, Serbia — Novak Djokovic and Viktor Troicki won their singles matches in straight sets to give Serbia a 2-0 lead against Spain in the Davis Cup quarterfinals on Friday.

Djokovic beat Albert Ramos Vinolas 6-3, 6-4, 6-2 and Troicki followed up to win 6-3, 6-4, 6-3 against Pablo Carreno Busta on an indoor hard court in Belgrade.

Djokovic returned to the court in style after an elbow injury that forced the No. 2 to withdraw from the recent Miami Open.

"I'm very satisfied with my play, especially my serve," said Djokovic, who led Serbia to its only title in 2010. "I like playing for my country."

Djokovic lost his No. 1 ranking to Britain's Andy Murray after a slump in form following his French Open title last year.

Five-time champion Spain was trying to make the semifinals for the first time since 2012, but doing so without its two highest-ranked players, Rafael Nadal and Roberto Bautista Agut.

Serbia needs a doubles victory on Saturday to reach the semifinals for the third time.

Troicki will be back on court to team up with 40-year-old Nenad Zimonjic against Marc Lopez and Jaume Munar.