WASHINGTON (AP) -- Bryce Harper hit the ball to the mound, jogged to first base and took a right turn to the dugout before getting halfway down the basepath.
First-year manager Matt Williams will tolerate physical miscues, such as the error that provided St. Louis three unearned runs, but he won't take the nonchalance that the normally aggressive Harper displayed during his sixth-inning jog.
''Lack of hustle. That's why he came out of the game,'' Williams said. ''He and I made an agreement, this team made an agreement, that when we play the game, that we hustle at all times.''
Now in his third season, the 21-year-old Harper is one of Washington's brightest lights and already a two-time All-Star. The outfielder once ran into a wall in the relentless pursuit of a fly ball, but on this day Harper was left explaining his casual approach on a comebacker.
''I respect what he did,'' Harper said of Williams' decision. ''That's part of the game.''
Harper was replaced by Kevin Frandsen, who entered as Washington's left fielder in the seventh and assumed Harper's position as the second batter in the lineup.
In the ninth inning, Frandsen came to the plate with runners on second and third with one out and Washington trailing 4-2. He drove in a run with a groundout before Jayson Werth struck out on three pitches against Trevor Rosenthal, who earned his fifth save.
''Kevin Frandsen put on a nice 'AB' against Rosenthal,'' Williams said, ''but (Harper's) spot came up with the ability to win the game. And that's a shame for his teammates.''
Said Harper: ''Man, that's tough to watch, not being able to be up there in that situation. It's something that I thrive on and I want to be in. You know, it's in the past and there's nothing we can do about it now.''
Williams said Harper would be back in the starting lineup Sunday for the series finale. Harper went 0 for 3 before being pulled and is batting .295.
''People come pay money to watch him play the way he can play,'' Williams said. ''And it's pretty exciting. It's pretty dynamic. But there's another side to it. And the other side is that regardless of how the ball comes off the bat or regardless of how he's feeling about an at-bat, he must maintain that intensity and that aggressiveness. And that means running all the way to first base and touching the base.''
Harper was scratched from a game Wednesday with a sore quadriceps, but Williams didn't view that as a reason to stop short of running 90 feet to first base.
''Regardless of situation, regardless of what's happening to you personally, we have to play the game a certain way to give ourselves the best chance to win,'' the manager said. ''And it's too bad that it came down to that situation in the ninth inning when he could've been at the plate. For the sake of his teammates and the sake of the organization, he needs to play with aggression and the way he plays.''
Lance Lynn (4-0) gave up one run and five hits over 5 2-3 innings in becoming the NL's first four-game winner. After the right-hander lost his control in the sixth, Kevin Siegrist retired Danny Espinosa on a two-out fly ball with the bases loaded.
Tony Cruz drove in two runs for the Cardinals, who have won nine of the last 10 games between the teams.
St. Louis took control with a three-run second inning fueled by third baseman Anthony Rendon's throwing error, capped by Lynn's RBI double. The Nationals, in their first season under former Gold Glove third baseman Williams, are averaging more than an error per game and lead the majors in miscues.
''I feel like we made a mistake, a couple of minor mistakes that cost us, but we were in the game,'' Williams said.
Espinosa homered for the Nationals, but he was the only player to get past first base against Lynn until the sixth.
Jordan Zimmermann (1-1) allowed four runs, only one of them earned, in seven innings. He struck out six and walked two after coming in with a 0-3 with an 8.27 ERA in six career games against the Cardinals.
St. Louis bolted in front for good in the second inning. After third baseman Anthony Rendon threw wide on a potential force play at second, Cruz sliced a two-out, two-run single to right field and scored on a double by Lynn. It was the pitcher's first extra-base hit in 115 career at-bats and his fourth RBI.
NOTES: The game drew a sellout crowd of 41,084. ... The Nationals activated OF Denard Span from the 7-day disabled list and optioned OF Steve Souza Jr. to Triple-A Syracuse. Span started in the leadoff spot and got two hits. ... Stephen Strasburg (1-2) starts for Washington on Sunday against RHP Shelby Miller (1-2), who went 2-0 against the Nationals last year.