The Phillies added four prospects -- three of them pitchers -- to the 40-man roster Tuesday before the deadline to protect them from selection in the Rule 5 draft.

Righthanders Trevor May, Jonathan Pettibone, Ethan Martin and outfielder Zach Collier are the additions. They push the Phillies' 40-man roster to 38 players.

May, Pettibone and Martin were locks for inclusion. May, 23, entered 2012 rated as the organization's top prospect by many but stumbled to a 4.87 ERA at double-A Reading. Pettibone, 22, finished the season at triple-A Lehigh Valley to rave reviews. Martin, 23, was acquired in the Shane Victorino trade and posted a 3.18 ERA in seven starts with Reading.

All three of those young starters could be in the Lehigh Valley rotation come April.

Collier's addition was not as certain until his spectacular stint in the Arizona Fall League. The former first-round pick hit .371 with seven extra-base hits over 19 games in the showcase league. Collier, 22, missed the first 50 games of the season because of a suspension for adderal and has overcome numerous injuries.

The four players are automatically invited to big-league spring training with their addition to the 40-man roster.

The most notable unprotected player is righthander Julio Rodriguez, who represented the Phillies last July in the annual Futures Game. Rodriguez, 22, dominated the Florida State League in 2011 without overpowering stuff but did not handle the jump to double-A Reading with success.

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