The Seattle Mariners announced seven non-roster invites for spring training on Monday.

Right-handed pitchers Dylan Unsworth and Andrew Moore, catchers Tyler Marlette, Marcus Littlewood and Sebastian Valle, second baseman Tyler Smith and outfielder Tyler O'Neill will start camp with the big league squad. Pitchers and catchers will report Feb. 14 and position players will join them Feb. 18.

O'Neill is the highest-regarded prospect of the group. He ranks as the No. 2 prospect in the Mariners organization, per ESPN's Keith Law.

O'Neill, 21, was a third-round pick in 2013. He hit .293 with 24 home runs for Double-A Jackson last season.

Unsworth and Marlette also topped out at Double-A last season. Littlewood split time between Double-A and Triple-A and Smith played all of last season at Triple-A. Valle played for the New York Yankees' Double-A affiliate last season.