Serena Williams and Venus Williams were beaten 2-6 6-1 10-8 by Marta Kostyuk and Peyton Stearns in a gripping first‑round doubles contest at the Cincinnati Open, marking their first match together since the 2022 US Open.   The sisters, competing as wild cards, returned to the doubles court after four years apart, having been forced to abandon a planned reunion at Wimbledon earlier this summer when Serena suffered a knee injury during her singles defeat. Their comeback in Cincinnati with Serena aged 44, Venus 46. Drew a packed crowd eager to witness one of tennis’ most decorated partnerships back in tandem.…