NEW YORK — Baseball and its players’ union defended their drug testing program Friday and promised to tighten collection procedures following criticism by anti-doping agencies of an arbitrator’s decision to overturn NL MVP Ryan Braun’s 50-game suspension.

At a news conference in Phoenix, where he reported to the Milwaukee Brewers for spring training, Braun criticized drug testing by baseball as “fatally flawed,” citing the roughly 44-hour lag between when his urine was collected and when it was given to Federal Express for transport to a laboratory in Montreal.

The drug agreement between management and the Major League Baseball Players Association calls for the sample to be sent the same day “absent unusual circumstances.”

While Braun left open the possibility that the delay could have led to his sample being altered, Major League Baseball Executive Vice President Rob Manfred said “neither Mr. Braun nor the MLBPA contended in the grievance that his sample had been tampered with or produced any evidence of tampering.”

David Howman, director general of the World Anti-Doping Agency, called the delay a “technical breach” and was disappointed arbitrator Shyam Das ignored the substance of the case.