WASHINGTON — Zach Eflin can exhale.

Two days after leaving a start after 80 pitches because of soreness and tightness in his surgically repaired right knee, Eflin learned he has only a bruise and should be able to start Sunday in the Phillies’ series finale with the Washington Nationals.

Eflin had surgery last September on a torn patellar tendon in his right knee, his second such procedure in five years. He did much of his rehab while being unable to communicate with Phillies officials, including trainers, for 99 days during MLB’s lockout, and began the season on time, even after a shortened spring training.

So, the Phillies were concerned that Eflin may have aggravated the patellar tendon in Tuesday night’s start at home against the Miami Marlins. But after a series of diagnostic tests, doctors determined the tendon was not damaged.

“That’s really what we were worried about,” interim manager Rob Thomson said. “So it was good news.”

Eflin is scheduled to throw a bullpen session Friday. If all goes well, he will face the Nationals. Eflin has a 3.96 ERA in 61 innings over 11 starts this season. He avoided an arbitration hearing last month by signing a one-year, $5.7 million contract with a $15 million mutual option for next year.

After Tuesday night’s game, Eflin expressed optimism that it wasn’t anything serious. He said his knee began to loosen up with treatment from the athletic training staff.

“At the end of the day, I’m still 8½ months post pretty major knee surgery. There’s going to be peaks and valleys throughout this process,” Eflin said, noting that he went through similar issues after surgery in 2016. “But I’m not too worried about it.”

The Phillies’ starting pitching depth would be tested with an injury to any member of the rotation. They don’t have much experience in triple A to back up Zack Wheeler, Aaron Nola, Eflin, Kyle Gibson, and Ranger Suárez.

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Getting to know you

Get ready to see the Nationals a lot over the next three months.

When the original 2022 schedule came out, the Phillies were slated to play in Washington on April 4-6. But the owners’ lockout and protracted labor talks caused a postponement of the season’s first two series.

The result: Nineteen of the Phillies’ final 99 games — 19.2% of the remaining schedule — will be against the Nationals.

It should work to the Phillies’ advantage. Entering play Thursday night, the Nationals had a 23-42 record, worst in the National League, and were on pace to lose 104 games.

But could familiarity between the teams level the playing field?

“I don’t know,” Thomson said. “Some people say [it favors] hitters, some people say pitchers. I don’t know.”

Wheeler, who started for the Phillies on Thursday night, has said previously that he doesn’t typically like facing the same team twice in a row or three times in one month. The teams play each other seven times in September, although Thomson noted that rosters may look different by then.

Extra bases

Utility infielder Johan Camargo (strained right knee) went through a full workout and could begin a minor-league rehab assignment within the next few days. He may be activated next week. ... After a recent setback, reliever Sam Coonrod (strained right shoulder) has resumed a throwing program at the Phillies’ complex in Clearwater, Fla. ... If the Phillies win the series in Washington, it will be the first time since 2011 that they have won at least five series in a row. ... Suárez (4-4, 4.40 ERA) will start the opener of Friday’s doubleheader against Nationals right-hander Joan Adon (1-10, 6.95). Left-hander Bailey Falter (0-2, 4.20) will be added to the roster from triple A, as expected, to start the nightcap against Nationals right-hander Paolo Espino (0-1, 2.08).

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