NEW YORK — In between coughing spells Sunday morning, Bryce Harper, his voice sounding like someone who isn’t in a state to play a baseball game, explained he’s been sick for about a week. The illness, Harper said, has worsened over the past three days, over which he’s gone 0 for 11 with a walk. As a result, he’s not in Washington’s lineup against the New York Mets Sunday.

Harper insisted he’ll be in the lineup Monday against the Philadelphia Phillies at Citizens Bank Park, where he’s hit 13 home runs and posted a .958 OPS in 44 career games.

Meanwhile, Juan Soto, another candidate for a day off, is in Washington’s lineup for the 45th straight game. The 19-year-old left fielder last wasn’t in the Nationals’ lineup July 4. He’s started 82 games and played in 84 games since getting called up on May 20. Only Trea Turner has appeared in more games during that stretch than Soto, who has appeared in 124 games between the minors and majors this season after playing in 83 career games before this season.

Manager Dave Martinez said he suggested giving Soto a day off to him on Sunday, but the rookie was adamant about playing and was “100 percent” sure he was ready to play Sunday.

Soto went 2 for 4 Saturday, but his recent play suggests he may be tiring. Since Aug. 5, Soto has batted .212 with a .691 OPS in 20 games. He’s still compiling walks at a high rate — 15 in 82 plate appearances — but has just four extra-base hits. He had two hits Saturday, but was thrown out attempting to stretch a single into a double in the eighth inning with two outs and the Nationals down 2-0.

“When he starts swinging at pitches all over the place, you tend to think that’s a good indication that he’s tired and his focus is not there,” Martinez said. “But he’s been good.”

In bullpen news, Ryan Madson and Sean Doolittle were both scheduled to throw bullpens Sunday. While Doolittle’s return isn’t imminent, Madson could come off the disabled list as soon as Monday in Philadelphia. Madson is recovering from lumbar nerve irritation and rejoined the club Saturday after spending a week in Phoenix rehabbing with his trainer.

NATIONALS (64-66)
Adam Eaton RF
Trea Turner SS
Anthony Rendon 3B
Ryan Zimmerman 1B
Juan Soto LF
Michael A. Taylor CF
Wilmer Difo 2B
Spencer Kieboom C
Jefry Rodriguez P

METS (58-71)
Amed Rosario SS
Jeff McNeil 2B
Michael Conforto LF
Todd Frazier 3B
Jay Bruce 1B
Austin Jackson CF
Jose Bautista RF
Tomas Nido C
Steven Matz P

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