McCann's leadoff homer off Edwin Jackson in the second inning proved to be enough for Sheets, who scattered five hits over six scoreless innings. The former All-Star has completed 12 scoreless innings in his two starts since returning to the Majors.
Given that Sheets had essentially been retired since tearing the flexor tendon in his right elbow two years ago, it is safe to assume he has exceeded the expectations the Braves had when they signed him to a Minor League contract earlier this month.
But the results have not completely shocked the confident veteran, who was one of the game's top pitchers before his dominant days with the Brewers were interrupted by shoulder and elbow injuries.
"If you ask me if I'm surprised I haven't given up a run, yeah I am. But I'm not surprised I'm getting people out. I wouldn't have come back if I didn't think I could get people out."
The Braves added an insurance run in the eighth inning, with some help from Henry Rodriguez, who allowed Michael Bourn to score on a wild pitch. But Chipper Jones might have delivered the key blow when he drilled a first-pitch, two-run home run after coming off the bench as a pinch-hitter in the ninth inning.
Jones' home run off Ryan Mattheus allowed the Braves to avoid using closer Craig Kimbrel, who had worked each of the three previous days. But because Kimbrel warmed up, he likely will not be available for the nightcap.
"I think the most important thing is that in the last eight games in our division, we've taken care of business," Jones said. "That's the way you make hay, winning games within your division."
These last few days have been good for the Braves, who erased a nine-run sixth-inning deficit on the way to claiming an 11-10, 11-inning win in Friday night's series opener. With 10 wins in their past 12 games, they have moved within 1 1/2 games of the first-place Nationals in the National League East.
After losing six of the first eight games played against the Nationals, the Braves have opened this four-game series with two consecutive victories. Sheets and Kris Medlen, who provided two scoreless innings of relief, helped keep Atlanta's bullpen fresh heading into the nightcap of Saturday's doubleheader. Chad Durbin finished things off with an unblemished ninth inning.
"Certainly [Friday night's] game you chalk up as a fluke because that doesn't happen very often," Jones said. "But to back it up with a solid performance today, you get some momentum going. I can't think of a better day to have a doubleheader with as nice a roll as we're on right now."
McCann got the Braves rolling when he drilled Jackson's 0-1 fastball over the right-field wall to open the second inning. The veteran catcher has hit seven of his 16 home runs in his past 10 games and distanced himself from the frustration that built as he batted .225 with a .379 slugging percentage in his first 63 games of the season.
Around the time McCann started turning things around during the first week of July, Sheets was in Atlanta to coach his son's baseball team and throw a bullpen session for four teams at Georgia Tech. Braves general manager Frank Wren made the five-minute drive from Turner Field to watch the side session and signed the 34-year-old pitcher a few days later.
Before throwing six scoreless innings against the Mets last Sunday, Sheets had not pitched in a Major League game since July 19, 2010.
"He still knows how to get guys out and stay off the sweet spot," Jones said. "I think you'll see him gradually gain a [tick] or two with his velocity as he gets stronger, more comfortable and logs some innings. That's going to make his curveball that much better. He made big pitches when he had to and he got a couple double plays that got him out of jams."
Sheets surrendered consecutive two-out singles in the first inning before notching one of his six strikeouts against Nationals first baseman Adam LaRoche.
"His velocity isn't what it used to be, but he's made up for it with location, mixing pitches up," LaRoche said. "He keeps the ball down. We just couldn't get to him."
Along with displaying an effective curveball, Sheets also used his two-seam fastball to induce double-play groundouts in the third and fourth innings. With two on and no outs in the third inning, he got the dangerous Michael Morse to hit into the first of those double plays.
"He's in total command on the mound and knows exactly what he's trying to accomplish," McCann said. "He's been around a long time. The more guys like him you have around, the better off your team is going to be."