The Phillies announced their $4.5 million signing of righthander Roberto Hernandez on Wednesday and jettisoned a former prospect to make room for their newest pitcher.

Catcher Sebastian Valle was designated for assignment because the 40-man roster was full. Valle, who was the fifth catcher on the team's depth chart, fell out of favor in recent years.

Valle, 23, ranked as high as third on Baseball America's rankings of the Phillies' top prospects. That was prior to the 2012 season. Since then, Valle posted OPSes of .699 and .603 while at double-A Reading for the majority of time. He struggled with plate discipline but displayed a raw power stroke.

Valle platooned with Cameron Rupp at the start of last season. Rupp played his way into a promotion to triple-A Lehigh Valley and, later, a September call-up to the majors. He performed well in Arizona Fall League play and figures to be the team's first reserve at catcher should Carlos Ruiz or Wil Nieves falter.

Tommy Joseph's future as a catcher is uncertain because of concussion problems, but he too eclipsed Valle. Other candidates for removal were lefthander Joe Savery and outfielders Tyson Gillies and Zach Collier.

Valle, once signed for $30,000 out of Mexico, can still return to the Phillies on a minor-league contract if he chooses. He must clear waivers, be traded, or released in 10 days. The Phillies attempted to trade him to Houston last winter in the failed Wilton Lopez deal.

Hernandez can earn an additional $1.5 million in performance incentives.

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