HARRISBURG, Pa. -- In the makeshift press conference room set up behind the team store filled with replicas of his jersey, Stephen Strasburg sat down at the table and shrugged.

He had surely wanted what could be his last start in Double-A to be masterful, in front of a standing-room only crowd here at Metro Bank Park on a warm Sunday afternoon. Instead, he revealed his pitching mortality.

When his day was done -- after 4 2/3 innings, six hits, four runs (three earned), three walks, and four strikeouts -- Strasburg's professional record had its first blemish.

He took the loss in his fifth career start, as Harrisburg fell, 6-1, to Altoona. And for the prized 6-foot-4 right-hander, the No. 1 pick in last year's First-Year Player Draft, it was a learning moment.

"There's always going to be days when things just aren't going your way," Strasburg said.

For the first time since he arrived here, Strasburg battled through adversity -- a tight strike zone from home-plate umpire Jon Byrne, a quick-trigger Altoona lineup jumping after his fastballs, some defensive miscues by the infielders behind him and a bout of wildness even on a sunny day in central Pennsylvania.

He threw 79 pitches (49 for strikes) and was relieved with runners on second and third in the fifth inning.

"I did what I could do," Strasburg said. "I think they squared one ball up on me. It's just one of those days where you make a good pitch and you get weak contact [and] it just finds a hole."

No, this was not a gem, not a masterpiece as fans had come to expect from Strasburg through four starts at the Double-A level. It was pitching, in the form taken 98 percent of the time by those on the mound, and it was a test the 21-year-old phenom was bound to face.

Strasburg hit his troubles in the second inning, as Altoona loaded the bases with nobody out, and Alex Presley drove in two runs with a single to right field. Two more runs scored on a fielder's choice and an errant throw by second baseman Michael Martinez.

Strasburg threw 30 pitches in the inning, and another 21 in the third, and as he walked off the mound, he had some words with home-plate umpire Byrne.

"Every umpire has a different zone," Strasburg said. "You've just got to keep pitching where you want to put it. I was doing that, I just wasn't getting the call."

On Saturday, MLB.com reported that it was likely Strasburg will be promoted to Triple-A Syracuse after this start, barring a poor outing or any unforeseen occurrence Sunday. It is unclear whether or not his performance will alter those plans.

Strasburg said he didn't know what would happen.

"All I know right now is that I'm going to show up to the field tomorrow, play some catch, get ready for my bullpen [session] and get ready for my next start," Strasburg said.

Until Sunday, though, Strasburg was simply overpowering through his first four starts. He had allowed only seven hits, three walks and one earned run in 17 1/3 innings, and he was coming off a five-inning no-hitter against Reading on Wednesday. His ERA was 0.52.

If it is indeed Strasburg's final start in Harrisburg, there is no measurement of the impact he's had on this community team in the new ballpark on City Island outside downtown Harrisburg.

Senators general manager Randy Whitaker said he's never seen the way a Double-A prospect has attracted such attention, save for a young outfielder in the Minor Leagues when he was in Memphis 25 years ago named Bo Jackson.

"I don't even think Bo was as big a deal as Strasburg has been," Whitaker said.

"It's not just community, this is nationwide. We've got people from miles, coming from Long Island, Michigan, all kids of places for this. It draws locally big, but this kind of transcends a community baseball team."

The team's director of merchandise, Ann-Marie Naumes, said sales go up three times as much when Strasburg is on the mound. They've sold out of his authentic jerseys (at $220 apiece) and nearly all 1,000 of the T-shirts they ordered before the season.

"We sell baseballs, photos, pretty much anything with him on it," Naumes said.

Whitaker said he'll be sad to see Strasburg go when the inevitable move is made, and the electricity in the stadium noticeably left when Strasburg made his exit in the fifth. The crowd gave him a standing ovation as he walked off the mound.

They applauded because it may be the last they see him here, even if his performance wasn't as pristine as they were expecting.

For the young pitcher, the time may have come to take a step forward even after suffering his first step back.

"It's been a great experience; it is a great experience here," Strasburg said. "We have a really great team, I think we work really well together, we just haven't put things together."