After another underwhelming start, what's next for Giolito?

Three starts into Lucas Giolito's career, the only thing the Nationals know for sure about their 22-year-old pitching prospect is that they don't really know yet what they've got.

Giolito arrived in the big leagues late last month with a near-flawless pedigree. He had the stuff, the maturity and the presence to suggest he was ready for the big show.

The results, though, haven't matched up with the pedigree. And now, following another underwhelming performance yesterday during what became a 10-6 loss to the Padres, Giolito appears to be even more of an enigma.

"It's back to the drawing board with him," manager Dusty Baker said.

The drawing board, in this case, is going to include another stint in the minors. After the game, the Nationals informed Giolito he was being optioned to Triple-A Syracuse, where he'll attempt to refine the arsenal of pitches that he has struggled to harness in his limited time in the majors.

The 22-year-old's primary task now: Learn how to command his secondary pitches (curveball, changeup) with far more regularity than he has displayed thus far.

"It's frustrating, because my last outing at Syracuse, I was commanding off-speed pitches pretty well and I had a good outing," he said Sunday. "I didn't translate that into today, obviously. I just have to keep working and try to get better at it."

It has been a problem for Giolito in each of his last two starts for the Nationals, not as much in his rain-shortened debut June 28. He hasn't been able consistently to throw his curveball and changeup for strikes. That forces him to rely too heavily on his fastball, which in return is getting hit quite hard.

During yesterday's game, Giolito managed to retire the first six San Diego batters he faced. But then eight of the next 11 he faced reached base safely, four via well-struck base hits.

This was a problem at times for the right-hander during the season's first half at Double-A Harrisburg. The difference: He was able to get away with it more often in the minors than he has in the majors.

"The big thing is you have to command off-speed pitches: curveball, changeup," he said. "Commanding the fastball is a given, but you're going to get in trouble when you don't command those pitches. When you can't throw a curveball for a strike, or a changeup in a hitter's count, then you get into trouble. And I've been dealing with a lot of that."

Giolito also has been dealing with this surprising development: He's not missing bats.

Of his 66 pitches thrown yesterday, only one was a swing-and-miss strike. He did not strike out anybody. And in 11 innings across three starts, he has just five strikeouts.

Put that all together, and you've got a rookie who has yet to reach the fifth inning in any of his three major league starts.

And there's no telling when his next start at this level will come. Giolito's demotion yesterday was made to clear a roster spot for reliever Sammy Solis, who is due to come off the disabled list Tuesday.

The Nationals will need to add a starter back to the mix by Saturday, though. Giolito is ineligible to be recalled for 10 days, unless he's replacing a newly injured teammate. Joe Ross is progressing in his return from shoulder inflammation, but the right-hander threw only 43 pitches in a three-inning rehab start yesterday for low-Single A Hagerstown, so he is all but certain to need at least one more tune-up.

That leaves Reynaldo Lopez as the likely choice to rejoin the big league rotation. The 22-year-old flamethrower had an erratic debut for the Nationals during this last homestand, giving up six runs and 10 hits in 4 2/3 innings, but striking out nine while issuing only one walk. He was demoted the next day but pitched a gem yesterday for Syracuse: a four-hit shutout of Rochester that included seven strikeouts and zero walks.