MOSCOW, Russia - With the Porsche Race to Singapore coming down to the wire, former US Open champion Sloane Stephens has ensured that she will be part of the final act's battle by taking a wildcard into next week's Kremlin Cup.

The BNP Paribas WTA Finals Singapore presented by SC Global field will only be determined in the last week of play, and Stephens - currently No.6 in the Race - is not mathematically safe from Elina Svitolina, Karolina Pliskova or Kiki Bertens snapping at her heels. The American came out of this year's Asian swing with two first-round exits, in Tokyo and Wuhan, and a third-round showing in Beijing.

The Roland Garros finalist's wildcard means that she can take her Singapore destiny into her own hands on her debut appearance in Moscow, where Pliskova and Bertens will also be competing and where World No.1 Simona Halep has already accepted a wildcard.

Elsewhere, former World No.1 Garbiñe Muguruza has received a wildcard into next week's BGL BNP Paribas Luxembourg Open. The Spaniard, who today reached the semifinals of the Prudential Hong Kong Tennis Open with a 6-2, 7-5 win over Luksika Kumkhum, will be making her second appearance in the Grand Duchy. Back in 2012, a 19-year-old Muguruza came through qualifying - defeating Johanna Konta 4-6, 6-3, 7-5 en route - before falling 4-6, 6-2, 6-1 to Andrea Petkovic in the first round.