Hyun-Jin Ryu’s fine form figures to leave Dodgers with tough decision in October

Reporting from PITTSBURGH —  The dichotomy between the sixth and seventh inning of Thursday’s 5-2 Dodgers victory underscored a dilemma facing this team as October approaches.

For six innings, left-handed starter Hyun-Jin Ryu stymied the Pirates and held them to one run. In the first inning after he departed, left-handed reliever Tony Watson gave up a run-scoring single to a left-handed batter.

In six starts since the All-Star break, Ryu owns a 1.54 earned-run average. Watson, along with fellow new addition Tony Cingrani, has been shaky since joining the club at the trade deadline. The Dodgers have yet to determine who their primary left-handed reliever will be in the postseason.

Could it be Ryu?

“Right now, I’m not too concerned,” Ryu said. “I’m just concerned about my next outing. As a starting pitcher, if I can put my team in a position to win, I believe I’m doing my job. [Joining the bullpen is] not what I can control. That’s not a decision I have to make.”

After undergoing shoulder surgery in 2015, Ryu pitched once in 2015 and 2016. He has returned in fine form this season, with an ERA of 3.34 for the year. However, because of his shoulder history, the team cannot inject him into the bullpen without worry.

If the team does want Ryu to relieve, he will have to try in September. But pitching coach Rick Honeycutt said that because of Ryu’s extensive pregame routine, which has been developed to activate his surgically repaired shoulder, it won’t be easy for Ryu to adapt to the bullpen.

“It would be a tough thing to be more of a one-inning guy, plus he never went on back-to-back days, those type of things,” Honeycutt said. “I think it would be unfair to him to ask him to be able to do that.”

The Dodgers cannot guarantee Ryu won’t be needed for the postseason rotation. Three of the pitchers projected to start ahead of him — Clayton Kershaw, Yu Darvish and Alex Wood — are on the disabled list. All three should rejoin the team within the next two weeks, and Darvish is scheduled to start on Saturday, but each has a recent history of injury.

When the season began, some people in the organization projected Wood to become a primary setup man for Kenley Jansen. Wood out-performed expectations and earned a spot on the All-Star team as a starter. His recent bout with inflammation in his sternum could cause the team to reconsider using him as a reliever, depending on how he performs when he returns.

“From now until the postseason, we have some tough decisions to make,” manager Dave Roberts said. “That’s the thing we have to deal with, when you have a lot of good players. There’s going to be some tough conversations.”

Short hop

Kershaw took a flight home to Dallas for a day with his family before heading to triple-A Oklahoma City for a four-inning, 60-pitch rehabilitation start.

andy.mccullough@latimes.com

Twitter: @McCulloughTimes