MOSCOW, October 17. /TASS/. Russian tennis star Maria Sharapova was knocked out of the 2017 VTB Kremlin Cup tournament in Moscow after suffering a straight sets defeat in the tournament’s first round on Tuesday to Slovakia’s Magdalena Rybarikova.

Rybarikova, seeded 8 at the tournament, ousted wildcard-invited Sharapova from the Moscow tournament in the first round packing the straight sets victory of 7-6 (7-3); 6-4.

It was their second career head-to-head meeting on Tuesday. In their first encounter at the WTA tournament in Mexico’s Acapulco in 2015, Sharapova outlasted Rybarikova 6-1; 4-6; 6-1.

This year’s Kremlin Cup was the fourth in Sharapova’s tennis career. She previously played at the Kremlin Cup tournaments in 2005, 2006 and 2007 and her best result was the quarterfinal stage.

The annual VTB Kremlin Cup tennis tournament is held on October 14-22 at Moscow’s Olympic Stadium and puts $1.6 million in prize money up for grabs.

On Sunday, Sharapova won the Women's Tennis Association (WTA) final game against Belarus’s Aryna Sabalenka in China’s Tianjin, scoring 7:5, 7:6 (10:8). The 2017 WTA Tianjin Open was the first tournament for Sharapova to win since May 2015.

Sharapova is Russia’s most decorated tennis player having won a total of five Grand Slam tournaments, namely the Australian Open in 2008, the French Open in 2012 and 2014, Wimbledon in 2004 and the US Open in 2006. She also clinched the silver in the 2012 Summer Olympics in London and was the 2008 Federations Cup champion.

After a 15-month long suspension for violating anti-doping regulations, Sharapova made her comeback to tennis in April at Stuttgart, where she stormed into the semifinals round of the tournament.