Pershing Square founder Bill Ackman made his professional tennis debut. In a doubles match at the Tennis Hall of Fame Open, he and his partner lost in straight sets in a match that lasted just 67 minutes. Some tennis greats were sharply critical of the match.

“I feel like maybe it’s one and done,” Mr. Ackman said, in the wake of his and Mr. Sock’s 6-1, 7-5 defeat, noting he wanted to support younger players getting their tournament slots — and shots.