PHILADELPHIA (CBS) – When Roy Halladay decided to call it quits in December, he became the first member of the best pitching staff in Phillies history to retire. There will now be a pair of aces who will no longer be in the dugout.

Former Phillies pitcher Roy Oswalt has decided to retire, according to ESPN’s Buster Olney.

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Oswalt will work with his agent, Bob Garber.

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In one and a half seasons with the Phillies, Oswalt went 16-11, with an ERA of 2.96. Oswalt went 163-102 in his 13 year MLB career, the majority of which was spent with the Astros (10 years). The Phillies traded for Oswalt in 2010, in a deal that included JA Happ, Anthony Gose and Jonathon Villar.

Oswalt went 0-6 with the Rockies in 2013, with an ERA of 8.63.

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