It will be a good test for the Phillies, who have won six of their last nine games.
It also will be Victorino's first opportunity to see Nationals rookie Bryce Harper in a big league uniform.
Victorino and Harper both reside in Las Vegas in the offseason, and Victorino has occasionally worked out with the 19-year-old phenom. He said he likes Harper, who has a reputation for being arrogant or cocky.
"He was in the outfield and he was asking questions and wanting to learn," said Victorino, who worked out with Harper just before they left for Spring Training in February.
"We were talking baseball. He was very humble. I can see where people are going to feel that way about him. Like I say the same thing too. Like, really? Come on, Bryce. But I look at it like at 14 years old, this guy was known as the best player in the country. And in all of his life, that's all he's ever known. So he has to go out there with some kind of confidence.
"Again, some of the things he's done I disagree with, but it's a learning process," Victorino added. "What impressed me most about the kid is he wants to work hard. He wants to learn. He has all the talent in the world. I haven't been in camp with him. I'm just going off working with him in the offseason, living in Vegas and hitting with him. I've definitely seen a maturity over the years of working out with him. ... From what I've seen so far of his big league performance, I love the fact he's playing the game hard. That's important to me. Not just slacking. But don't get me wrong, I want to take it to him when I see him this week."
So, who has the better arm?
"I got him," said Victorino, who belted a two-run homer to cap the Phils' 4-0 win over the Braves on Thursday.