Wearing the number nine shirt, the big striker put his country ahead in the sixth minute, then headed home his second after 23 minutes. He played for 77 minutes as Serbia went top of Group D.
The Newcastle man had been an unused substitute in their 3-0 win over Moldova on Thursday.
In the same group, the Republic of Ireland recorded victories over Georgia (1-0) on Thursday and Moldova (3-1) on Sunday. Ciaran Clark played the full 90 minutes in both games but Daryl Murphy missed out through injury.
Achraf Lazaar played for 87 minutes as Morocco drew 0-0 with Gabon on Sunday while Paul Dummett was an unused substitute in Wales' 1-1 draw with Georgia, just as he had been as Chris Coleman's side earned a 2-2 draw in Austria on Friday.
Grant Hanley and Matt Ritchie both started as Scotland drew 1-1 with Lithuania at Hampden Park on Saturday. Hanley played the whole game, setting up a late equaliser for James McArthur and picking up a yellow card, while Ritchie was replaced in the 71st minute. Scotland take on Slovakia on Tuesday evening.
Mo Diame helped Senegal to a 2-0 win over Cape Verde on Saturday. He played for the opening 62 minutes. DR Congo beat Libya 4-0 with Chancel Mbemba playing the full game.
On Friday, Christian Atsu was part of the Ghana side which drew 0-0 with Uganda while DeAndre Yedlin started for the USA in a 2-0 friendly victory in Cuba and Matz Sels was an unused substitute as Belgium beat Bosnia 4-0.
Adam Armstrong and Callum Roberts also remained on the bench as England under-20s recorded a 3-1 win against their German counterparts - but on Thursday evening, Freddie Woodman made his England under-21 debut and kept a clean sheet in a 1-0 victory against Kazakhstan.