ST. LOUIS -- Gerrit Cole is out, Francisco Liriano is in, but the Pirates' conundrum remains the same: What to do as the trade deadline approaches about a rotation that has a surplus of pitchers performing well, but also uncertainty about health?
Liriano will come off the disabled list, where he has spent a month because of a strained left oblique, and rejoin the rotation without making another rehab start, manager Clint Hurdle said Tuesday. Liriano cannot return until Saturday against the Reds in Cincinnati because he made a rehab outing Monday, pitching six scoreless innings and striking out eight without walking a batter for Class AAA Indianapolis.
"He got sharper as the game went on," Hurdle said. "Fastball velocity was good, 91-95. The changeup played, the breaking ball played."
Hurdle said the Pirates had not decided whether Liriano would pitch Saturday or Sunday. Charlie Morton's turn in the rotation comes Saturday and Vance Worley is on track for Sunday.
Cole will go on the DL because of what he has referred to as tightness in his right latissimus dorsi, or lat. Cole said he did not feel like himself in a bullpen session Monday at Busch Stadium after first feeling tightness in the lat in his previous start Friday.
"I was looking forward to pitching, but they just were really convincing in the fact that we need to look at the bigger picture," Cole said. "I was kind of out of options."
The lat issue is different from the shoulder fatigue that forced Cole to the DL in early June.
Hurdle said he does not think Cole's injury will require a lengthy recovery, but said Cole will need to make at least one rehab outing before returning. Hurdle also stressed the importance of ensuring Cole is fully healthy before coming back.
"We want to just keep him in a position where the understanding, when he comes back, it's an opportunity to thrive, not survive," Hurdle said. "Not navigate lineups. Pitch instinctively, not have a checklist before every pitch and a checklist after every pitch. Where he can go out and be the Gerrit Cole that we've seen in the past. I don't feel that's far away."
Liriano, Morton, Worley, Jeff Locke and Edinson Volquez will comprise the rotation when the Pirates resume play after the All-Star break with about two weeks remaining before the trade deadline. Entering Tuesday's game, the rotation had a 2.71 ERA in the past 30 days, second best in the National League behind the Los Angeles Dodgers.
"There's not a glowing hole for us, whether it's in the rotation or the bullpen or the position-player club," general manager Neal Huntington said Sunday before Cole was placed on the DL. "That doesn't mean we're not going to work to try to find a way to make ourselves better. When Liriano comes back, we're going to have a guy that probably deserves to be in a major league rotation not be in a major league rotation."
Huntington said the recent success of the rotation hasn't stopped the Pirates from communicating with other teams about trades.
Bill Brink: email@example.com and Twitter @BrinkPG.