MIAMI — The Phillies will name their Saturday starter after Thursday's game, and it is expected to be David Buchanan. There are few other options, especially in the wake of continued shoulder woes for Jonathan Pettibone.

Pettibone consulted Wednesday with renowned orthopedist James Andrews. He diagnosed the 23-year-old righthander with a small SLAP lesion, a type of labrum tear which is considered a serious injury depending on its size. Andrews presented Pettibone with three options: an exploratory arthroscopic surgery, a platelet-rich plasma injection, or a cortisone injection.

The pitcher opted for cortisone. He will rest until May 31 and then resume a throwing program. There are no guarantees, though.

"It's a small tear," Phillies general manager Ruben Amaro Jr. said. "Basically it's how long he can manage through it."

The problem is Pettibone has battled shoulder soreness since last summer. The Phillies injected him with cortisone in February. That proved to be a temporary solution. He made two starts for the Phillies in April and could not match the effectiveness displayed during his rookie season in 2013.

Amaro noted many pitchers have thrown with labrum tears. Mets righthander Dillon Gee suffered a partially torn labrum in 2009 and never had it surgically fixed. The procedure to repair a SLAP tear is complex and would sideline Pettibone for the remainder of 2014.

Pettibone will attempt to strengthen the muscles and tissue around the labrum. Some will heal, Amaro said; others do not.

"It depends on the player and how big it is," Amaro said. "It's not a big one. It's pretty small. But it's uncomfortable for him."

Pettibone's health is an issue because the Phillies lack considerable starting depth in the minors. Buchanan was left unprotected for the Rule 5 draft last winter and became one of the last players invited to major-league spring training. He impressed team officials with his poise and command in the spring.

The 25-year-old righty posted a 3.98 ERA in nine starts at triple-A Lehigh Valley.

"He hasn't been dominant," Amaro said. "But he's been consistent and he's winning."

For now, that is enough to make him the Phillies' fifth starter.

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