Weronika Falkowska and Katarzyna Piter lost 6-4, 6-4 to Heather Watson and Yanina Wickmayer in the doubles final.
The Women's Tennis Association said it was aware of the situation.
The player was taken into custody in the southern Polish region of Silesia, prosecutors said in a statement. The player and his team were not publicly identified.
The van maker, a division of Mercedes-Benz, has signed a declaration of intent with the Polish government and other partners to add the van factory to its Jawor site where it makes combustion engines and batteries for Mercedes-Benz Cars.
Giroud became France's all-time top scorer and Mbappe struck a a brace for the holders.
Olivier Giroud had put France ahead in the first half. Robert Lewandowski managed a late consolation for Poland.
Argentina's victory moved the South American side to the top of the group and they will face Australia in the last-16 while second-placed Poland take on reigning champions France.
The matches are set to start at 8.30 pm and 12.30 am (IST).
The Saudis were without defender Yasser Al-Shahrani, who underwent surgery back home following a severe facial and abdomen injury in the first match, and captain Salman Al-Faraj.
Robert Lewandowski's 58th minute penalty was only the second shot on target Poland had all game.