WASHINGTON -- A line drive from Jesús Aguilar’s powerful bat smacked off the back of Max Scherzer's right throwing shoulder and ricocheted to second base. Hit at 98.9 mph, the first-inning liner looked painful.

“Thankfully it was a glancing blow, and I’m just more happy that it didn’t hit me in the head,” Scherzer said. “That ball was coming right back at me, and fortunately I was able to turn and it caught me on the backside of the shoulder.”

In typical determined Scherzer fashion, he stayed in the game, but his outing would end with some hard hits, just like it began. Scherzer threw 108 pitches over 4 2/3 innings, allowing seven hits (one homer), four runs and two walks while striking out five in the Nationals’ 5-4 win over the Marlins in the opener of Saturday’s doubleheader at Nationals Park.

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“I was able to kind of keep it loose, and I was able to still pitch on it, still able to get through the ball, so you just continue to march on,” Scherzer said. “Fortunately it didn’t do as much damage given that the location of that spot could be pretty bad.”

Scherzer and the Nationals were eyeing a deep outing just hours after the club announced Stephen Strasburg will undergo season-ending surgery for carpal tunnel neuritis in his right hand. If Scherzer could keep the bullpen fresh, that would be a bonus on the afternoon of a doubleheader and in the early stages of the Nats’ stretch of 21 games in 19 days.

The Nationals offense built up a 5-0 lead, including an RBI from Howie Kendrick in his first game since Aug. 14, while Scherzer kept the Marlins’ bats at bay through four.

Scherzer ran into road blocks, though, with two outs in the fifth. Magneuris Sierra, who had doubled with one out, scored on a Jonathan Villar single two batters later. Scherzer gave up a homer to Matt Joyce -- then surrendered back-to-back singles to Aguilar and Corey Dickerson, hit Brian Anderson to load the bases and walked Jesús Sánchez to make it a one-run game. That ended Scherzer’s sixth start of the season, and reliever Kyle Finnegan escaped the bases-loaded jam with a strikeout of Jorge Alfaro.

“In the fifth inning, there were a couple batters I had bad location on,” Scherzer said. “The other couple times, I didn’t hit my spot and they were able to get a hit and extend the inning. When it got down to, when you really needed an out -- say against Anderson and Sánchez -- I just wasn’t able to get the job done, wasn’t able to locate. Obviously had a hit by pitch and walked somebody on four straight, so that’s on me.”

Giving the Nationals meaningful innings is important for Scherzer. It’s not just about reaching triple-digit pitches, it’s also about being as efficient in later frames as he is in early ones. In his last start on Sunday in Baltimore, he pitched seven innings. The Orioles plated three in the sixth and one in the seventh. Scherzer was assessed with all of their runs.

“I believe I can pitch in tough spots in the game, even late in the game, even when my pitch count’s above a hundred,” Scherzer said. “I still believe I can execute in those situations. Unfortunately, the past couple games, I haven’t done that and I need to get better at that.”

The fact Scherzer stayed in the game for as long as he did should come as no surprise. The strong-willed ace has been tested physically this season. He previously dealt with a tweaked right hamstring, which caused him to exit after one inning on Aug. 5 against the Mets. When asked about the ailment following his last start on Sunday, when he fanned 10 in seven innings, Scherzer stressed, "That's over. It's over."