Maria Sharapova becomes Polymarket's first celebrity partner for US Open
Polymarket has launched an advertisement featuring tennis star Maria Sharapova amid a surge in tennis trading activity during the US Open. The spot comes as both Polymarket and Kalshi pursue sports partnerships around the tournament. Sharapova is the platform's first celebrity partner. Tennis has led sports trading volume on both platforms during the event. Kalshi holds the official US Open prediction market partnership.
Sharapova gives Polymarket a recognizable face to compete with Kalshi's official US Open partnership and ESPN court-side visibility. The two platforms are now running parallel tennis marketing plays from different angles: Kalshi owns the tournament badge, while Polymarket bought the athlete personality. That split forces traders to choose on product depth and fees, not brand monopoly.
Novig's $125 million debut week adds a third sports venue pulling flow, so marketing alone will not retain users if spreads widen or liquidity thins. The real test is whether Sharapova converts audiences beyond political traders into repeat sports bettors, a demographic Polymarket has not fully cracked. Kalshi must now respond with its own celebrity hire or risk letting Polymarket control the athlete endorsements in this space. Rival platforms face a higher customer acquisition cost if star power becomes table stakes.