They seemed like the perfect circumstances.

The Phillies had Cole Hamels on the mound yesterday against the Washington Nationals at Citizens Bank Park. If they could have Hamels be Hamels - he struck out 15 Saturday in Cincinnati - and the offense could pound the ball as it had for the last week, they would sweep the Nationals, who own the worst record in baseball, and make it six straight wins.

But then Nationals righthander Shawn Hill showed up to silence the offense, and Hamels lost his composure in the sixth inning of a 4-2 loss.

The Phillies won the series, two games to one. But to reach their goal of a winning April, they would need to sweep the Florida Marlins this weekend and beat the Atlanta Braves on the road Monday.

"The goal is to win the series," said third baseman Wes Helms, who had two of the four hits against Hill. "Yeah, we're let down. We wanted a sweep and we had a five-game winning streak going. But you take two out of three every series and you're going to get back over .500. And, second of all, you're going to be at the top of the division."

The Phillies would need to take two of three from Florida, Atlanta, Arizona and the Chicago Cubs, and split a four-game series in San Francisco, to get above .500 before May 14.

That leaves little room for error.

They had no room for error against Hill.

Hill had thrown seven shutout innings when Aaron Rowand crushed a leadoff homer to left-center field in the eighth to make it 4-1. The homer extended Rowand's hitting streak to a career high of 14 games.

But Hill otherwise gave the Phillies nothing but fits.

"He threw a hell of a game," Rowand said. "He's got great stuff. He's got a great sinker. He's got one of the best sinkers in the league, between him and Brandon Webb. He throws it hard. He hits his spots with it."

Catcher Rod Barajas, who caught Webb in Arizona, agreed with Rowand's assessment. So did Helms.

Hamels matched Hill early. But he allowed a solo homer to Dmitri Young in the fourth to make it 1-0, and got himself in trouble in the sixth.

Ronnie Belliard and Ryan Zimmerman hit back-to-back singles to lead off the inning, and Hamels uncorked a wild pitch to advance the runners to second and third. Hamels intentionally walked Austin Kearns with one out to load the bases, but Ryan Church fisted a single into left field to make it 3-0.

Hamels then did something uncharacteristic: He walked Michael Restovich to load the bases and walked Brian Schneider to make it 4-0.

"I tried to push a little bit more. I rushed," Hamels said. "I got into a few counts that I didn't have the first five innings. So when guys got on, I got a little antsy and tried to pump it up and blow pitches by guys. And to do that, I was rushing on my mechanics, and that messed me up."

Hill walked Shane Victorino to lead off the ninth and was replaced by closer Chad Cordero, who blew a save against the Phillies last week in Washington. Chase Utley flied out to the center-field wall, but Ryan Howard doubled to put runners on second and third with one out.

Pat Burrell's sacrifice fly scored Utley to make it 4-2. But there would be no blown save this time.

Despite the loss, manager Charlie Manuel remained encouraged.

"We're playing a lot better than we were, but we've got three games left on this homestand and we've got to come out and win tomorrow," he said.

Contact staff writer Todd Zolecki at 215-854-4874 or tzolecki@phillynews.com.