Moscow, Russia, 19 October 2017 | AAP

Fatigue and injury have combined to curtail Daria Gavrilova’s Kremlin Cup campaign – and possibly her hopes of qualifying for the Elite Cup.

Gavrilova was forced to retire hurt from her second-round match against Vera Lapko, trailing 6-3 3-1 to the Belarusian qualifier in Moscow when she pulled the pin shortly after a medical timeout.

Meanwhile, injury appears to have played a role in Nick Kyrgios’ loss at the European Open in Antwerp.

The world No.20 won a tense first set but was beaten 6-7(3) 6-3 6-3 by Belgian Ruben Bemelmans in the second round of the ATP indoor event.

Neither player earned a break point in the first set, which was dominated by serve. Kyrgios pounded down 14 aces but world No.98 Bemelmans relied on his heavy left-handed serve to hold Kyrgios at bay.

The Australian third seed, who received a bye in round one, appearing to struggle with a hip injury as the almost two hour contest progressed and he called a medical time during the second set.

From that point world No.98 Bemelmans took control of proceedings to record an impressive victory.

Gavrilova still hoping for Zhuhai berth

Gavrilova, with her left hamstring already heavily strapped, received treatment on her right leg and after the world No. 167 Lapko held serve to extend her lead, the 23-year-old Aussie walked to the net and shook her opponent’s hand.

The prestigious $US2.3 million Elite Cup takes place in China from 31 October and features players ranked ninth to 19th at the end of the WTA’s 2017 points race.

US Open champion Sloane Stephens and fellow Grand Slam champions Angelique Kerber and Svetlana Kuznetsova have already qualified.

Gavrilova is 22nd in the points race and needed to at least reach the quarterfinals in Moscow – where she was runner-up last year to Kuznetsova – to have any chance of automatically qualifying.

But there is still hope for the Aussie – ninth-placed Johanna Konta announced she was shutting down her season while 11th-placed Svetlana Kuznetsova and 16th-placed Madison Keys are under injury clouds, potentially elevating Gavrilova in the standings.

Ash Barty, who is training this week ahead of her appearance in doubles with Casey Dellacqua at the WTA Finals in Singapore, is currently 19th in the race and in line to qualify in Zhuhai after landing her maiden singles title (Kuala Lumpur in February) and reaching two other finals in a breakout season.

Moscow-born Gavrilova has enjoyed the best season of her career, winning her first WTA tournament in New Haven, in August.

She has also reached two finals including last week’s Hong Kong Open, losing a titanic three-hour decider to world No.18 Anastasia Pavlyuchenkova.

Less than 48 hours later, Gavrilova was on court against Kristyna Pliskova following a 10-hour flight to the Russian capital.

What looked to be a routine win over the Czech left-hander became a gruelling encounter before she finally prevailed 6-4 6-7(5) 6-1 having squandered five match points in the second set.

Gavrilova then had to back up in the third match on the day on Wednesday and subsequently struggled throughout, gift-wrapping the biggest win of the young Belarusian’s career.

“My body is very confused what time zone it’s in?!?!?!?!?!?,” Gavrilova tweeted after the match.