Turin, Nov 16 (IANS): The Green Group action climaxes on Thursday at the Nitto ATP Finals, with both qualification spots for the semi-finals still up for grabs. Novak Djokovic will bid to bounce back from a defeat to Jannik Sinner, knowing a win against alternate Hubert Hurkacz would go a long way towards extending his Turin title defence beyond round-robin play.

Djokovic was turned back by home favourite Sinner in a thrilling three-setter on Tuesday night, but the Serbian left the match proud of his efforts.

The defending champion now faces a fight to advance out of the group stage. While his matchup with alternate Hurkacz is not technically a "must win", Djokovic would put himself in prime position to return to the semi-finals by improving to 2-1 on the week — particularly if his victory is an emphatic one.

Hurkacz will enter this matchup with nothing to lose, entering for the final group match as a replacement for Stefanos Tsitsipas (back injury). But the Pole will still be playing for considerable Pepperstone ATP Rankings points and prize money as he seeks to finish his season with a win against the World No. 1.

The Pole reached the Rolex Paris Masters quarter-finals in his last appearance, bowing out after a three-set defeat to Grigor Dimitrov — whom Djokovic beat in the final.

While Djokovic faced a barrage of big serves against Sinner on Tuesday, his returning prowess may be put to an even tougher test against the power of Hurkacz, who is the runaway ace leader on the ATP Tour with 1,031 this season. Like Sinner, Hurkacz will be seeking his first Lexus ATP Head2Head win against the Serbian.