By now Esteban Loaiza has heard the question so many times, considering it, pondering it and digesting it enough to know there is no proper answer. So yesterday he just shrugged.

"Do you feel you have to be perfect?" he was asked.

And the Nationals number two starting pitcher, a man who could well have 19 wins right now were it not for an anemic Washington offense, gave a small laugh. What could he say?

"When you're perfect, things can go bad," he said.

Yesterday he made what he thought was close to a perfect pitch to San Diego pitcher Jake Peavy -- a slider curling away from home plate. And Peavy, a mild offensive threat for a pitcher, reached out and blooped Loaiza's near-perfect slider into center field for a single that drove in the first run of the game.

Which was, given the state of things around the Nationals, the only mistake he was allowed to make. The moment he allowed a run, his eighth loss was sealed. Washington never mounted a true scoring threat against Peavy, save for putting runners on first and second with two outs in the sixth, with an about-to-be-demoted outfielder named Matt Cepicky at the plate.

"That's baseball," Loaiza later sighed. "I don't feel no pressure when I pitch. I just go out there and pitch my game -- I threw 83 pitches in seven innings. I wanted to keep going, but my spot came up in the order in the seventh and the manager wanted to pinch-hit for me. I tell him I can keep going, I want to finish the game and have a chance to win, but he's the manager."

Increasingly, things are getting more challenging for the Nationals' starters, who continue to deliver sparkling starts only to have their efforts go to waste when the offense fails to produce. With yesterday's 3-0 loss to the Padres, Loaiza is now 6-8 with a 3.63 ERA. Washington's third starter, John Patterson, is 5-3 but could easily have another 12 victories. Last weekend, after a 3-0 loss to the Florida Marlins, he was asked the same question. Did he feel he had to be perfect?

"Absolutely, we have to go out and be perfect," he replied.

The fact is, no one is perfect. And there will be moments like yesterday's when Peavy hit the slider that Loaiza said was moving well. There, too, will be pitches like the change-up he threw Padres left fielder Eric Young, another pitch that Loaiza thought was pretty good, yet one Young smashed into the second deck in left field for a home run.

With the way the Nationals are going, a pitcher can't make any mistake like that.

Later, Washington Manager Frank Robinson complained about those very same pitches that Loaiza thought were good enough. Young had only 71 at-bats at the time, Peavy was hitting .171 coming into the game and a second Padres home run was hit by Xavier Nady, who has been a part-time player.

"You can't make those little mistakes, you've got to be perfect," Robinson said. "And it's tough to be perfect."

Loaiza also didn't help himself when he got picked off second by catcher Miguel Olivo with nobody out in the third inning. But that alone shouldn't have doomed Washington.

"It's just another day, what can I say?" Loaiza said. "I've just got to hang in there."

Pitcher Esteban Loaiza looks around for some offense, but found none -- again -- in a loss to the Padres.