Nick Pivetta will return to depleted Phillies rotation against Chicago

This has not been a kind month for the Phillies rotation. The starters, in August's first 24 games, posted a 5.82 ERA. Just two teams in baseball were worse. The momentum from a July that produced a 3.66 ERA by the starting staff did not carry.

The unit is young. The Phillies will make a roster move to add Nick Pivetta, who will start the series finale Sunday against Chicago. Pivetta, 24, has a 6.73 ERA in his 19 starts. He could not pitch beyond the second inning in his last start.

"He's got a lot of work to do," Phillies manager Pete Mackanin said. "Let's put it that way."

The Phillies have decided that work is best accomplished in the majors and not at triple-A Lehigh Valley.

"I think it boils down to who's available," Mackanin said.

The choices for current rotation arms are limited. The Phillies demoted Jake Thompson after his mediocre outing earlier in the week. They have kept righthanded prospect Drew Anderson on the 25-man roster as an extra arm for a few days, but prefer him to gain more seasoning before he enters a major-league rotation. Vince Velasquez, Zach Eflin, and Clay Buchholz are hurt. Jeremy Hellickson was traded. Elniery Garcia, who is on the 40-man roster, is not long removed from a drug suspension. Another, Mark Appel, is injured.

Thomas Eshelman, 23, has pitched well at triple A. But he is in just his second full professional season and does not yet need to be added to the 40-man roster. The Phillies are content with his finishing the season in the minors.

So, for now, Mark Leiter Jr. will hold a spot in the rotation. He has pitched well enough to keep it. Leiter will start Tuesday against Atlanta, after Aaron Nola goes Monday.

"In the end, he very well might be one of our starters, but he's so valuable in the other role he's played in," Mackanin said of Leiter. "That role is quite important too — the swing man, the guy that can give you length.

"He's made a real good impression, but there's a guy who doesn't throw 95-plus. He's got six different pitches and he commands them."

The Phillies could add at least three starters — Franklyn Kilome, Ranger Suarez, and Seranthony Dominguez — to their 40-man roster this winter. Only Kilome has reached double-A Reading.

This is all leading to a logical conclusion: The Phillies will acquire a few veteran starters to serve as stopgaps in the 2018 rotation.

"I think we have to upgrade," Mackanin said.

The front office is, by all accounts, in agreement. They have added two veteran starters on one-year commitments in each of the last two winters. Expect that plan to continue this winter.

Odubel Herrera took batting practice with the team Saturday and could soon be activated from the disabled list. Herrera was eligible to return Friday, but the Phillies are taking it slow with his strained left hamstring. … For a few hints as to who could join the Phillies in September, check the Lehigh Valley lineups. J.P. Crawford started his second straight game at second base. He started five games at third base before that. And Carlos Tocci, a deft centerfielder, started in left field Saturday for just the second time in his career. … Pivetta will face Cubs veteran righty John Lackey in Sunday's matinee.