A crowded Phillies rotation?

Phillies pitcher Tyler Cloyd. (Jim Mone/AP)

The Phillies will make a change to their starting rotation Tuesday, and it figures to be the first of many alterations in the coming days.

Tyler Cloyd will be recalled to start against Colorado. He replaces John Lannan, who could miss the remainder of the season with a knee injury. Meanwhile, Roy Halladay and Jonathan Pettibone will each make their second minor-league rehab starts Tuesday. Both could soon return.

Halladay, of course, is the arm everyone will watch. He makes a start for single-A Lakewood after throwing 87 pitches for the Gulf Coast League Phillies. He should approach 100 pitches in this start, but now it is less about stamina and more about results.

Initially, Ruben Amaro Jr. said Halladay could require just two starts before his return to the majors from shoulder surgery. His performance Tuesday will dictate whether that prediction holds.

Pettibone, sidelined by shoulder soreness, could be ready after this latest game. He threw 72 pitches for double-A Reading last week. The 23-year-old rookie is not guaranteed a spot in the Phillies rotation, but he pitched well enough to merit more chances.

Cloyd has pitched with sharpness in recent weeks. He has a 1.33 ERA in his last seven starts with 32 strikeouts and five walks in 47 1/3 innings. The Phillies know what Cloyd, 26, provides. He relies on pinpoint control because his high-80s fastball will not overpower anyone.

The odd man out could be Ethan Martin, who starts Monday against the Rockies. Martin, 24, appears headed for a future in the bullpen. The Phillies could expedite that process with a transition in September and discover whether he could be a cog in 2014.

Phillies starters have a 5.92 ERA since the all-star break. Remove Cole Hamels' six solid starts and that number jumps to an unsightly 7.43.

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