O'Neill, the Mariners' No. 2 prospect, according to MLBPipeline.com, is one of just three non-pitchers or catchers among the players invited in addition to those on the 40-man roster. Outfielder Kyle Waldrop, who played 15 games for the Reds last year, is one of the veteran non-roster additions. Shortstop Tyler Smith, ranked 29th, is also coming to camp for a second straight year.
Moore, the club's No. 8 prospect, is among the 10 non-roster pitchers invited. Other right-handers are Christian Bergman, Cody Martin, Micah Owings, Max Povse, Peter Tago, Dylan Unsworth and Ryan Weber.