The Potomac Nationals, Washington's Class A affiliate, had just finished the final game on their schedule. Detwiler was outside the dugout signing autographs for fans when one of them offered him unsolicited congratulations.
"What are you talking about?" Detwiler asked.
"You got called up to the Majors," the fan replied. "I just heard it on the radio."
Detwiler met moments later with his manager, who confirmed the good news from the unexpected source. Less than two months after signing with Washington, the right-hander out of Missouri State was heading to the big leagues.
"It just didn't seem real at first," he said.
Three days later, Detwiler made his Major League debut, tossing a scoreless inning of relief against the Braves.
He hasn't appeared since, and neither he nor Washington manager Manny Acta is sure when or how often the 21-year-old will pitch again. But Detwiler, who went 2-2 with a 3.51 ERA in nine appearances between Potomac and the Rookie League's Gulf Coast Nationals, is happy just to be along for the ride.
"It's been sinking in coming to the field every day, being around everybody," Detwiler said. "It's an unreal experience. You always dreamed about this [when] growing up and now, it's actually happened."
The Nationals' stated intent for bringing Detwiler up was much less about evaluating his arm and much more about getting him acclimated to the inner workings of a Major League team.
"He's not trying out," Acta said. "He's just gaining some experience."
Detwiler, the sixth overall pick in the 2007 First-Year Player Draft, signed a contract on July 6 that included a $2.15 million signing bonus. He's the first member of the 2007 Draft class to reach the bigs.
"Everybody's just been real accepting of me," he said. "Once I came in, they accepted me as one of them."
Except, of course, for some standard rookie hazing. The pink, child-sized backpack hanging in Detwiler's locker isn't a voluntary fashion accessory; he and the other callups have been forced by teammates to parade them around before games. Detwiler was also forced to read a made-up story about his childhood to fans from the bullpen in Atlanta.
"It's nothing too bad," Detwiler said with a smile. "I'm just waiting for them to dress me up."
Ready, set, wait: Catcher Brian Schneider was out of the lineup in favor of Jesus Flores for the third straight game on Monday, but this time, it had nothing to do with the flu.
Schneider said he felt close to 100 percent Monday, but Acta opted to play it safe and give his starting backstop another day off. Acta said Schneider will catch the final two games of the series.
The presence of left-hander Scott Olsen on the mound for Florida on Monday also influenced the decision. Flores is hitting .273 against lefties; Schneider just .210.
Flores has made the most of his recent spike in playing time, having gone 9-for-21 with five RBIs over his last six starts. Acta said the opportunity to see more of Flores has been mutually beneficial.
"It's good for [Flores] to play consecutive days," he said. "We want to give him more at-bats."
Righting the ship: Chad Cordero has quietly worked into one of his longest grooves of the season.
Since allowing four runs and taking the loss at Colorado on Aug. 24, Cordero hasn't allowed a run in his last seven innings, tied for his second longest scoreless stretch of the season. During that span, the right-hander has struck out nine, walked two, allowed just four hits in 24 at-bats and passed the 30-save mark for the second time in his career.
"I can't ask for a better job," Acta said. "He's done what we've asked him to do."
See and believe: Few people know what reliever Arnie Munoz is capable of. Acta is one of those in the know.
The Nationals manager worked with Munoz in Dominican winter ball the past few seasons, so he's well aware of the left-hander's repertoire. Now, with Ray King gone, Munoz will get more of an opportunity to showcase what Acta has already seen.
"Munoz has the pitches and the ability to get hitters out," Acta said. "He's got to prove it now to the rest of the people that don't know him. That's what this month is going to be for him."
While Acta acknowledged that winter ball doesn't boast hitters of as high caliber from top to bottom, he said they're good enough to provide a reasonable gauge of Munoz's staying power.
"David Ortiz is an OK hitter, too," Acta joked. "[Munoz] didn't compete with [winter ball hitters] -- he dominated them. That's why maybe here he'll be able to compete [with Major League hitters] and adjust to them."
On deck: The Nats and Marlins will tangle again at 7:05 p.m. ET on Tuesday. Mike Bacsik (5-8, 4.74 ERA) will oppose Chris Seddon, who will be making his first Major League start.
Tom Keller is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.