On Monday, Rob Manfred, the new commissioner of Major League Baseball, got a chance to extricate his sport from a deepening moral quandary. Pete Rose, the disgraced onetime star of the Cincinnati Reds, petitioned Mr. Manfred’s office to be reinstated in the sport from which he was barred in 1989 for gambling.

Mr. Rose, 73, was the most dynamic player of the last half-century and, after that, a first-rate manager. He played more games (3,562) and got more hits (4,256) than anyone else ever.

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