"It was just a great catch at a great time," Souza said.
Souza entered the game in the bottom of the ninth inning as a defensive replacement for left fielder Ryan Zimmerman. With two outs, Marlins outfielder Christian Yelich came to the plate. First-base coach Tony Tarasco was moving Souza toward the left-field line, and Yelich hit the ball to left-center field on a 2-1 pitch.
"I knew it was going to be extremely close, because I knew I was going to have to lay out and I was hoping I could get enough angle where I could make a good play," Souza said. "Once I got closer, I was like, 'Oh my gosh, this thing is going to be pretty close,' so I took off."
Center fielder Michael Taylor knew he didn't have a chance to catch the ball. But there was Souza, who dove and caught the ball like a wide receiver protecting history.
"It was just pure excitement, especially for [Zimmermann], for just the year he has put together, the year to cap off the whole team," Souza said. "To be a part of it, it just an honor to me. Every ball, I want hit at me. I just want to make the play for him.
"That catch is just a small part of the whole game. It's awesome what he did today."
After the Nationals mobbed Zimmermann for what he accomplished, they ran toward Souza in left field. There was Souza giving Zimmermann a big bear hug. What did the pitcher say to Souza after the spectacular catch?
"He just said, 'I love you. Great catch,'" Souza said.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the Time. He also can be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.