Giolito debuts vs. Harvey, defending NL champs

When top prospect Lucas Giolito makes his Major League debut Tuesday, he'll have himself a high-pressure assignment.

Giolito, whom MLBPipeline.com ranks as the No. 1 prospect in all of baseball, will take on Matt Harvey and the defending National League champion Mets in the second of a three-game series at Nationals Park.

"You've got to try to pretend it's just another game, whether you're playing at Nationals Park here or you're playing at your hometown field," Nats manager Dusty Baker said. "You've got higher stakes, more people, but you've got to put all those things out of your mind and realize you've just got to concentrate with throwing the ball over the plate."

The Mets' offense has struggled lately. They've scored five or more runs only once in their last 10 games and are ranked 22nd in team OPS in the Majors this season. The are also ranked near the bottom of the Majors in batting average.

Still, Giolito will have to contend with the nerves that accompany a Major League debut. Nationals ace Max Scherzer thought back Monday to his first MLB outing back in 2008, recalling he was "just anxious to get out there." He said Giolito's success or failure will depend less on his imposing stuff than on his mental acuity.

"At this level, you don't really judge on stuff because it takes so much more than stuff to be good, it takes what's going on between your ears," Scherzer said. "Everything we've seen this spring was that he's got a good head on his shoulders, so we expect good things out of him."

Giolito, who is pitching in place of the injured Stephen Strasburg, will face another former phenom in Harvey. The Mets' righty has bounced back from a mid-May skid to record strong starts in four of his last five outings. Over that stretch, Harvey has posted a 2.25 ERA and a .205 batting average against.

Things to know about this game
• Arguably Harvey's two worst outings of the season have come against the Nationals. On May 19 at Citi Field, he allowed nine runs (six earned) in 2 2/3 innings, and five days later he served up five runs in five innings at Nationals Park.

• The last time a starting pitcher drafted by the Nats began his career at Nationals Park came on June 8, 2010, when Strasburg struck out 14 Pirates hitters in a dazzling debut. Given that Giolito is nearly as touted a prospect as Strasburg was, the comparison is inevitable, but Nationals general manager Mike Rizzo emphasized that Tuesday will be no different from any other pitcher's MLB debut.

• With a single in the third inning Monday, Nationals catcher Wilson Ramos extended his hitting streak to 10 games. Ramos, who stood third among NL catchers in All-Star voting as of Monday, is second in the NL in batting average.