Shortly after being scratched from his start Friday night, the Nationals placed Max Scherzer on the DL. (Mike Ehrmann/Getty Images)

SAN DIEGO — Max Scherzer could laugh about the pain in the left side of his neck Friday night because it did not worry him. It was the same discomfort he felt nearly three weeks earlier when he removed himself from a game at Marlins Park after throwing 10 pitches and hitting a home run in the first inning. Only this time it was on the other side. He could laugh about it because he insists he and the Washington Nationals know how to alleviate the ache: with 48 hours of anti-inflammatories and persistent exercises.

He said he was dealing with the problem again after two typical Scherzer-type outings because he didn’t keep up with the neck exercises he was instructed to. So he woke up Thursday with the familiar discomfort, which worsened enough for the Nationals to scratch him a couple hours before his start Friday against the Padres and for Scherzer to go on the disabled list for the first time in more than eight years.

“This is my own fault,” Scherzer said after the Nationals pulled together a 7-1 win without him Friday. “Look, I was feeling good after this last start and I know it’s an excuse, and I hate excuses, but I forgot to do the neck exercises during this go around. And I know it sounds stupid, but it happened and for whatever reason this came back. Just need to stay on top of my program. Like I said, I’ve dealt with this in the past.  I know how to treat this. I know if you do everything, stay strong, this goes away. So stay on the anti-inflammatories, do your exercises, and this is a nonissue.”

Scherzer said he felt his neck tighten more when he hit in the batting cage Friday as part of his usual pre-start routine. He then threw and the discomfort remained. He knew at that point he couldn’t pitch. The Nationals then decided to place Scherzer on the disabled list and have Matt Grace make his first career major league start. The left-hander tossed 4 1/3 scoreless innings before five relievers pieced together the final 14 outs.

Scherzer’s first bout with neck trouble didn’t require a DL stint. He pitched again six days later and has looked like himself in his two starts since, yielding four runs over 14 innings and posting 19 strikeouts to three walks to continue making his case for a second straight Cy Young. Through Friday, the 33-year-old was second in baseball in ERA (2.25), first in WHIP (0.85), second in opponents’ batting average (. 171), second in strikeouts (220), and sixth in innings pitched (160 1/3).

With the DL stint, he’ll be forced to miss a start, but emphasized he won’t miss a second. He is eligible to return next Friday because his DL stint was backdated three days, and revealed that the Nationals’ plan is for him to start then against the Mets at Nationals Park. He said he’ll likely throw off a mound again Tuesday.

“I know what the cause of this is and I know it’s not anything serious,” Scherzer said. “Look, last time I went through this, the next time I was out there, I was at 114 pitches. I fully intend for that to be the case again on Friday.”

As the starting rotation stands, the Nationals do not need to fill Scherzer’s spot in the rotation because they’re off Monday before a three-game series against the Astros. If they keep the rotation intact using the off-day, Washington won’t need another starting pitcher until next Sunday’s doubleheader against the Mets.  Erick Fedde is the leading candidate for the start, and could be recalled as the Nationals’ 26th man. Fedde hasn’t pitched since allowing two runs in seven innings for Class AAA Syracuse on Aug. 13. His previous two outings were the first two of his major league career. He surrendered 11 runs in 9 1/3 innings against the Rockies and Cubs.

With Scherzer’s addition, the Nationals have 13 players on the disabled list — five outfielders, three infielders, two starting pitchers, and three relievers. Barring another injury or a setback, that number will drop to 12 Saturday when the Nationals activate Stephen Strasburg to start against the Padres.

It will be Strasburg’s first start since exiting after two innings against the Diamondbacks on July 23. He was put on the 10-day disabled list four days later with a right elbow impingement. He’ll be on regular rest Saturday after logging five innings on a rehab assignment for Class A Potomac on Monday.

“That’s been the story all year: We lose one and gain one,” Nationals Manager Dusty Baker said. “Hopefully, we’ll gain them all.”

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