With Sunday’s game between the Nationals and Marlins rained out, Stephen Strasburg and Dodgers ace Clayton Kershaw, above, aren’t expected to face each other. (Reed Saxon/Associated Press)

The Washington Nationals postponed Sunday’s series finale against the Miami Marlins at Nationals Park because of rain, derailing a delicious pitching matchup next weekend between Stephen Strasburg and Los Angeles Dodgers ace Clayton Kershaw but allowing Ryan Zimmerman the luxury of resting for three days while missing only one game.

After winning both games against the Marlins, the Nationals will carry a 12-4 record to the West Coast for a trip that begins Tuesday in San Diego. After playing 15 games in 15 days, the Nationals receive consecutive days of rest because of a scheduled day off Monday.

Manager Davey Johnson will not adjust his rotation schedule after the mini-break. “Nada,” Johnson said when asked about changes to the starting five. Gio Gonzalez, Jordan Zimmermann and Edwin Jackson will pitch in San Diego, with Ross Detwiler, Strasburg and Gonzalez starting over the weekend against the Dodgers.

Sunday’s rain robbed baseball of one of its juiciest pitching matchups this season. On Friday, Kershaw, the 2011 Cy Young winner, would have faced Strasburg. But now Strasburg will start Saturday and Kershaw will face Detwiler — still the seventh pick of the 2006 draft vs. the sixth pick of the 2007 draft, respectively.

This season, Kershaw has a 1.61 ERA with 22 strikeouts in 221 / 3 innings, while Strasburg has a 1.08 ERA with a league-leading 25 strikeouts in 25 innings. Both the Dodgers and Nationals have won all four games their ace has started.

Nationals starting pitcher Stephen Strasburg pitches against the New York Mets. (ADAM HUNGER/Reuters)

Johnson perked up for a moment when told the marquee matchup could have happened, but there was nothing he could really do about it. “Who do you want me to drop?” Johnson asked.

Even with Strasburg on a limit of roughly 160 innings this season in his first full season following Tommy John surgery, Johnson did not consider skipping Strasburg altogether in an effort to extend his season by a start or two. The Nationals have been adamant they will not manipulate Strasburg’s schedule in order to stretch out his year, and they stuck to that vow Sunday when given the chance to change it.

“One of the worst things you can do to any pitcher is too much time between starts,” Johnson said. “Regularity is what they know. Usually, your fifth starter is more a veteran guy. You would bump him and then keep your other guys more in line. But in this case, they’re all good. You just keep them in line.”

Still, Johnson has and will take Strasburg’s innings limit into consideration within his starts. Saturday, Johnson pulled Strasburg for a pinch hitter after he threw six scoreless innings while throwing 94 pitches, including 23 in the sixth. Johnson thought Strasburg could have pitched the seventh, but “that one more inning could be invaluable later in the year,” Johnson said Saturday.

“I don’t like that entering into the equation, and I’m sure he doesn’t either,” Johnson said Sunday. “. . . If he had an easy sixth, I would have given him one more inning. Now, later on in the year, I won’t be thinking about that.”

Zimmerman had planned to sit out Sunday’s game with right shoulder inflammation that convinced the Nationals to scratch him less than a half-hour before first pitch Saturday. Had the Nationals played Sunday, Chad Tracy would have played third base and batted third in Zimmerman’s place against Marlins ace Josh Johnson.

Between Saturday, Sunday and Monday’s scheduled day off, Zimmerman will miss only one game — which the Nationals won, 3-2, in 10 innings — while allowing the soreness in his throwing shoulder to die down. When Zimmerman woke up Sunday morning, he already felt improvement from Saturday, when he felt tightness while warming up in the batting cage.

“It feels much better, not that it was terrible every other day,” Zimmerman said. “These next two days will be nice. Tuesday, I really don’t see any reason right now why I wouldn’t play. It’s definitely nice. It’s very convenient, I guess you could say.”

Zimmerman remained unsure of when or how exactly the inflammation started. He knows he hurt his shoulder on a series of diving plays this homestand, including a leap into home plate while trying to score last Monday night against the Astros, on which he was tagged out.

“I have no clue when it started,” Zimmerman said. “I had a chance to dive for so many balls. The fourth-and-goal pylon dive into home probably didn’t help. But you can’t tell somebody, you can’t tell any of these guys, not to play that way. That’s just the way we’ve always been taught to play. No matter how many times you get hurt, that’s the only way I’m going to play.”

The Nationals have yet to announce the makeup date for Sunday’s game. Tickets for Sunday’s game can be exchanged at the Nationals Park box office for a ticket of equal or lesser value for the makeup game or for any other game during the regular season.