John Lannan nearing rehab assignment

John Lannan faced hitters in a simulated game Wednesday in Clearwater. (Michael Bryant/Staff Photographer)

Reinforcements to the Phillies rotation are coming, but the process is slow. John Lannan faced hitters in a simulated game Wednesday in Clearwater, Fla. He will pitch in extended spring training once more with the hopes of starting a minor-league rehab assignment June 6.

And veteran Carlos Zambrano, who pitched 4 1/3 scoreless innings at single-A Clearwater on Tuesday, will require at least three starts before he can contribute, Phillies general manager Ruben Amaro Jr. said.

That means Tyler Cloyd, who allowed six runs to Boston in 2 1/3 innings, will start again Saturday. He threw a bullpen session as scheduled Wednesday.

Amaro said the reports on Lannan (strained left knee) were encouraging. He was lukewarm on Zambrano's performance.

"He threw OK," Amaro said. "I don't think he lit the world on fire. But he's gaining arm strength. It was a little better than his last outing. He's getting stretched out. We'll see where he goes from here."

The Phillies must promote Zambrano to the majors before July 1 or he can ask for his release.

EXTRA BASES. Boston will not start ace Jon Lester as scheduled Thursday. Instead, lefthander Franklin Morales will make his 2013 debut. The Red Sox altered their rotation again because of Clay Buchholz's shoulder injury. ... Pitching prospect Adam Morgan has a shoulder injury that concerns the Phillies. He was seen by the team's doctor Tuesday and results were not immediately available.

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