WASHINGTON — One of the 43,470 people in the stands for Game 5 of the 2005 National League Championship Series was a high school senior from The Woodlands, Tex., named Paul Goldschmidt. He was up in the center field seats at Minute Maid Park, rooting for his favorite team, the Houston Astros, to advance to the World Series.

With one out to go, Albert Pujols launched a ball into orbit for the St. Louis Cardinals. The Astros, and Goldschmidt, had to hold off their celebration.

“I had a good view,” Goldschmidt said last week before a game at Nationals Park. “It was crazy. I was like every fan there. I was upset. But being in it, you know it’s just part of the game. You’re going to win some and lose some.”

Goldschmidt’s nonchalance belies an inner drive that has made him, for the first half of this season, Pujols’s heir as the most productive first baseman in the National League and a leading contender for the Most Valuable Player award. Goldschmidt is hitting .306 with 19 homers and a league-best 67 runs batted in for the Arizona Diamondbacks, who lead the N.L. West and visit Citi Field this week for four games against the Mets.