Before his bullpen session Friday, Brandon Kintzler was sure he wouldn’t need to pitch on a rehab assignment before being activated from the disabled list. The Washington Nationals right-hander’s first session, a 20-pitch exercise, had gone well a couple days earlier. His forearm strain wasn’t a problem. Wasting pitches for a minor league affiliate seemed superfluous.

But Kintzler emerged from Friday’s session — a simulated bullpen that included warming up as if preparing to enter a game — more fatigued than he expected. That told him he needed to pitch in a game somewhere before rejoining the Nationals so he’ll pitch for Class A Potomac on Sunday, joining Jeremy Hellickson, who is slated to start the game.

Kintzler said the plan is then for him to join the Nationals in Washington before they travel to Tampa, where they will begin a five-game road trip. The 33-year-old said he expects to be activated from the disabled list, which he’s been on since June 10, at some point during the week.

We have to “make sure he comes out of this okay,” Nationals Manager Dave Martinez said. “Once that happens, we’ll sit down and reevaluate how we’re going to use all those guys. But he’s definitely a big addition to our bullpen, for sure. . . . It’s nice to be able to match those guys up according to lineups and pinch hitters and stuff like that. He’ll still be at the back end of the bullpen along with all those other guys.”

“All those other guys” now includes Kelvin Herrera, the veteran right-hander the Nationals acquired from the Royals last Monday after a dominant start to the season. As a result, Kintzer could return to a different role.

The Nationals added him at the trade deadline last July primarily to pitch the seventh inning, a role he continued in this season. But a lack of depth forced the back end of the bullpen, to absorb a heavy burden early this season and the consequences were evident.

Kintzler landed on the disabled list. Ryan Madson hasn’t been nearly as good. Sammy Solis was pushed to the brink. So the Nationals traded for Herrera and quickly made him their eighth-inning reliever, bumping Madson down and giving Martinez more options to finish games. One could be inserting Kintzler in pivotal situations earlier in the game to extinguish jams in a sort of fireman role.

When Kintzler is right, he produces ground balls at a high rate with his go-to sinker. But he got away from throwing the sinker as often as he did in the past. Consequently, his groundball rate has dropped to 44.7 percent this season. Last year it was 54.9 percent. In 2016, it was 61.9 percent. Overall, Kintzler has posted a 4.45 ERA and 3.66 FIP in 28 1/3 innings this season.

“Brandon throws ground balls so a situation where we need a groundball, whether it’s the sixth inning, seventh inning, whatever, he’s the guy,” Martinez said. “When we need strikeouts, you have the other guys. He’s definitely a big part of our success moving forward.”

Another uncertainty surrounding Kintzler’s return is how the Nationals will create a roster spot for him. Washington is already carrying an eight-man bullpen and four-man bench so it can’t simply add a reliever at the expense of a bench player. Solis is the only reliever remaining with options besides Tim Collins, whose service time would allow him to decline the assignment.

Perhaps the move is optioning one of the two starters pitching Saturday and Sunday — Erick Fedde or Jefry Rodriguez — because Wednesday’s off-day affords Washington time to roll with a four-man starting rotation for one turn.

PHILLIES (40-33)
Cesar Hernandez 2B
Rhys Hoskins LF
Odubel Herrera CF
Carlos Santana 1B
Nick Williams RF
Scott Kingery SS
Maikel Franco 3B
Jorge Alfaro C
Aaron Nola P

NATIONALS (40-34)
Adam Eaton RF
Bryce Harper CF
Anthony Rendon 3B
Juan Soto LF
Daniel Murphy 1B
Trea Turner SS
Wilmer Difo 2B
Spencer Kieboom C
Erick Fedde P

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