Don Mattingly faces some tough calls for Dodgers’ postseason roster

Dodgers Manager Don Mattingly spent a good part of Friday afternoon in his clubhouse office, meeting behind a closed door with General Manager Ned Colletti. And with the team’s playoff opener less than a week away, it wasn’t hard to figure out what they were talking about.

“Our roster’s definitely not decided,” Mattingly said before his team’s 7-4 win over the Colorado Rockies. “We’ll have discussions, kind of going over different scenarios. I hate to say these are tryout games. But definitely you’re going to see disappointment with certain guys if they’re not on the roster.

“And we have to make some tough decisions.”

The toughest is likely to center on 14-game winner Hyun-Jin Ryu, who made two trips to the disabled list this season and is sidelined again with inflammation in his left shoulder.

Ryu threw off a mound Friday for the first time in two weeks. But the 20-pitch session, in which he appeared to have trouble with his off-speed pitches, did little to convince the manager the left-hander will be able to pitch in the playoffs.

“It’s hard to say it lines [him] up for anything at this moment,” Mattingly said. “But he’s moving in the right direction.”

If Ryu is pain-free Saturday, he will play catch, then throw a “max” bullpen session Sunday. And if he makes it through all that, the Dodgers probably would have him pitch a simulated game next week before deciding whether he can start Game 3 of the National League Division Series, scheduled for Monday, Oct. 6.

“All of those things still have to be crossed off,” Mattingly said. “So we have to plan accordingly. With him, without him, if he starts, if he can’t. All of those factors are still kind of up in the air.

“And that’s just going to depend on what happens over these next few days.”

If Ryu (14-7, 3.38 earned-run average) can’t go, the Dodgers would move Dan Haren up a day and have him start Game 3, then either use Clayton Kershaw on short rest in Game 4 or give a roster spot to Roberto Hernandez, who auditioned Friday against the Rockies.

It wasn’t a strong audition, though, as Hernandez needed 101 pitches to get through 5 2/3 innings, giving up three runs and six hits. But Mattingly felt different.

“He was a little bit better last game then he has been. I thought tonight this was the best that he’s been in a while,” Mattingly said of Hernandez, whose longest outing since joining the Dodgers in early August lasted just six innings. “He kept the ball down tonight. He threw more strikes.”

Another pitcher who didn’t help his case Friday was left-handed reliever Paco Rodriguez. He faced two batters and both reached base, on an error and a single. Right-hander Pedro Baez, on the other hand, saw his stock rise with a perfect inning of relief in which nine of his 12 pitches were strikes.

“Here’s the thing: You go over it, you go over it, you go over it. [But] you really don’t know which way it’s going to go,” Mattingly said. “Even after you’ve made the decision. It could be right, it could be wrong.

“You may go into a series and not take the extra pitcher and go, ‘Man, it would have been nice to have the extra pitcher.’ You might take the extra pitcher and never need him and it would have been nice to have the other guy. You really don’t know which way the games are going to go.

“So you do the very best with what you think and plan is the best.”

Ryu’s health will help determine a lot of that. If the Dodgers aren’t convinced he’s 100% or if they decide to give that start to Hernandez, they probably would load their bullpen with eight pitchers as insurance. And if they think they can get by with seven relievers, that would leave room for an extra infielder, giving Mattingly more flexibility to replace the defensively challenged Hanley Ramirez and Dee Gordon late in games.

The leading candidate for that spot is Darwin Barney, who improved his chances Friday with a leadoff single, a run scored and a scoring fly ball in a six-run sixth inning he entered as a pinch-hitter.

But Barney said he hasn’t taken a look at the roster math just yet.

“I try not to think too much about that kind of stuff and get into their job,” he said. “My job is to come here and get my work done and be ready to go.

“I never think of it that way. This is a weekend to get ready for what we have in front of us. I really haven’t thought of it on a personal level. I just thought about the team.”

kevin.baxter@latimes.com

Twitter: @kbaxter11